The American Society for Gastrointestinal Endoscopy really appreciates your participation in tonight's discussion, lesion characterization. My name is Michael Greenier and I'm going to be the announcer for this mini presentation. Before we get started, there's just a few housekeeping items. Currently everyone here is in the auditorium of our virtual environment. Any questions you have can be submitted at any time via the Q&A function that's at the bottom of your screen. And there will be about seven poll questions tonight that we really hope everyone can participate in. Now, it is my pleasure to introduce both our moderators for this evening, Dr. Kianam and Dr. Al-Khali, both chair and vice chairs of the Education SIG. Without further ado, I will turn tonight's event over to Dr. Al-Khali. Dr. Al-Khali? Yes. Thank you, Michael. Hello, everyone. This is our Endoscopy Education SIG and this webinar is for lesion characterization. And I really want to start by thanking everyone for the efforts, the ASGE guys, Michael and Eric, and of course, our legends and experts, Professor Yahagi from Japan and Professor Altman from USA. We know that they are super busy guys and however, they could manage to give us some time. And also, Dr. Kondal Kianam, the head of the Endoscopy Education SIG. And here is how we will proceed in the webinar. This, of course, our panelists, Professor Yahagi in Cairo University, Professor Altman Baylor University, Professor Kianam, Alabama University, and May Cairo University. So we will start after the introduction, we will go ahead with seven MCQ questions and I hope that all of you can participate. There will be a poll so you can press the button of what you think the right answer is. And we will not go into discussions or answers for this question. After the question, we'll go straight away with the presentation of Professor Yahagi about lesion characterization of upper GI lesions. And then afterwards, we will take the question and answer. And then afterwards, we will go with Professor Altman about lesion characterization for lower GI lesions. And then afterwards, we will take also another five minutes for question and answer. And we will end with a discussion of the previously answered MCQ question to see how could the experts change our way of thinking. Thank you so much. So with the first question, this is a 68-year-old male patient underwent EGD due to heartburn. As you can see, there is like a slight discoloration at five to three o'clock. So what do you think the most appropriate diagnostic modality as a next step? Is it biopsy, Leugel's iodine statin, MBI magnification or CT scan? So let's move to the second question. So this is a 43-year-old female patient who have this small depressed area indicated by the yellow R's around two centimeters. And the annual checkup biopsy from this area revealed signatory carcinoma. So what do you think the most appropriate next step of this patient? Shall we do chromoendoscopy, EMR, ASD, or go straight ahead to laparoscopic surgery? So here's another interesting case of a 63-year-old female patient who underwent EGD to do epigastric pain. So there's like a small protrusion in the posterior wall of the denal bulb and the biopsy revealed adenocarcinoma. So what do you think the treatment option that we should consider for this patient? Is it polypectomy, EMR, ASD, or surgery? So this is a 53-year-old male patient who underwent screening colonoscopy and it showed this lesion. How can you classify this lesion? Is it a granular LST, lateral spreading tumor? Is it PARIS 0-1S? Is it mixed granular and non-granular LST? Is it PARIS classification 0-2C? Is it non-granular lateral spreading tumor? This is an 82-year-old man underwent diagnostic colonoscopy for evaluation of iron deficiency anemia. This lesion was detected in his sigmoid colon. What is the most likely diagnosis? Is it a saccharated adenoma or polyp, well-differentiated adenocarcinoma, tubular vellus adenoma, tubular adenoma, or just hyperplastic polyp? So here is another 73-year-old female patient who had an ESD. She was referred for ESD. In this image, there is the narrowband image. According to the J-net classification, what do you think the type of this lesion? Is it J-net type 1, type 2A, type 2B, type 3? Or you cannot assess this lesion with a J-net? This is a 51-year-old female patient who had a screening colonoscopy. And this is during the terminal ileal intubation. You can see like areas was different, mucosal texture was observed. We have this blue arrow and the yellow arrow. What do you think? The blue arrow indicates adenoma and yellow is normal. Or the blue arrow is the normal and yellow is the adenoma, or both are normal tissue. Or the blue arrow indicates saccharated adenoma and the yellow is normal. So thank you, everyone. This was the quiz. And there are really some tough questions. And I hope by the end of this webinar, we can answer these questions properly. So I invite you all to enjoy the amazing lecture about lesion characterization for upper GI lesions with Professor Yahagi. Thank you very much for inviting me to this wonderful webinar. I'd like to share my slides. Well, I think that lesion detection is also very important for us. Therefore, I included lesion detection as well as characterization after detecting suspicious lesion. I have no COI to disclose. Well, this is my today's topic. I'm going to cover a spasial lesion for both skeletal cancer and adenocarcinoma. And for the gastric lesions, mostly adenocarcinoma. Duodenal lesions are also mostly adenocarcinomas. Well, there are lots of important technical tips when we conduct upper GI endoscope. But the most important technical tip is to clean the lumen before starting actual inspection. If there are lots of mucus and the dirty debris inside the stomach, we cannot see anything. Therefore, we carefully wash the lumen using cymaticon solution or pronase solution. Then we can easily find this kind of a tiny lesion. Otherwise, we easily miss this kind of relatively small and flat lesions. It's also the same in the esophagus. If there are lots of mucus inside, we cannot see very flat lesion. But after washing the salivary, we can easily recognize this reddish area. And when we switch on NBI, we can easily find this lesion as an extensive brownish area, which is typical appearance of schema cell cancer in the esophagus. Those kind of careful cleaning and observation is essential when we perform upper GI endoscope. Well, in the esophagus, we should learn typical appearance of superficial cancer, such as irregularity or discoloration of the mucosa. This is one of the typical example of the schema cell cancer in the esophagus. With the white light, you can easily see the reddish area. This is typical appearance of the schema cell cancer. And as I already shown you, when we use NBI, it turns to brownish area. And of course, when we spray iodine solution, it turns to unstained area. All those are typical appearance of schema cell cancer in the esophagus. Usually, after detecting target lesion, we should check the histology. But in the esophagus, majority of the schema cell cancer are well differentiated schema cell cancer. Therefore, in most of the case, we don't have to take actual biopsy. Just looking at the surface structure using NBI magnification or BLI magnification, we can easily understand the character of the target lesion by observing the dilated irregular IPCF. I will explain the details of IPCF pattern later. For the evaluation of the extent of the tumor, we can easily recognize the tumor extent by NBI. But we still use iodine solution just before conducting endoscopic resection because the mallocation line becomes much clearer after spraying iodine solution. For this purpose, we usually use 1% iodine solution, Lugol solution. If you spray more than 1%, such as 2% or 3%, it is too much. Because iodine is always stimulating the patient, it causes lots of discomfort, and sometimes it will cause lots of inflammation after spraying a high concentration of iodine solution. That's why 1% Lugol solution is ideal solution to spray when we evaluate the esophageal schema cell cancer. And of course, we have to assess the invasion depths when we select the candidate for endoscopic resection. If there is certain irregularity by the white light, it suggests already invasive cancer. But in many cases, NBI magnification is quite effective. Just looking at the irregular intrapapillary capillary loop, we can estimate the invasion depths. Actually, in Japan, esophageal society classification, it is categorized from A to B3. And if there is only tiny, linty IPCO, it suggests just inflammation, which is categorized type A. And when the loop formed, intrapapillary loop elongated, but still keeping the loop formation, it is categorized type B1, suggesting epithelial or laminar propylial cancer. Usually, this is very good candidate for endoscopic resection. And when the capillary loop lose the loop formation, it suggests a little bit deeper cancer, such as muscular ischemia or SM1, which is kind of borderline lesion. And if the capillary loop becomes really sick more than three times than the B2 capillary, it is categorized as B3 and suggesting really deep sub-mucosal or even proper muscle infiltration. That's why it is not endoscopic resection candidate anymore. And avascular area also suggesting tumor invasion. If the avascular area is very small, it suggests epithelial or laminar propylial cancer. But if the avascular area becomes a little bit bigger, up to three millimeter, it suggests muscular ischemia or SM1 lesion. And when the avascular area becomes much bigger than three millimeter, it usually suggests really deep sub-mucosal invasive cancer. Regarding the indication of endoscopic resection in the esophagus, we carefully check the invasion depths because risk for lymph node metastasis is extensively depending on the depth of tumor invasion. When the lesion depth is confined within epithelium or laminar propylial mucosa, the risk for lymph node metastasis is less than 5%. Therefore, it is really good candidate for endoscopic resection. But when the lesion embedding to the muscular ischemicosa or shallow sub-mucosal layer up to 200 micron, which is categorized type B1, B2, JES classification, it is kind of relatively indication for endoscopic resection because it already have some risk for lymph node metastasis up to 15%. And of course, when we find the B3 vascular network, it already become really high risk population, which has nearly 50% of lymph node metastasis risk. Therefore, it is already out of indication for endoscopic resection. Well, I would like to show you some of the example of typical skeletal cell cancer in the esophagus. Now you can see the reddish area on the right side wall. And it turns to brownish when we switch on NVI. And NVI magnification showed typical appearance of dot-shaped vascular network or slightly elongated loop-formed vascular network, which is categorized type B1. It usually suggests epithelial or lamina propylial cancer. Therefore, we decided to perform ESD as a curative intention. And it was actually epithelial cancer size two centimeters. And this is another example, which was really extensive skeletal cell cancer. You can see the reddish area with white light and it turns to be brownish area when we use NVI. And next step is close observation using magnification. This is really important because we have to know the character of the target region by looking at the IPCL. Majority of this target region presented dot-shaped capillary loop or slightly elongated loop-formed capillary loop. This suggests epithelial or lamina propylial cancer, which is a very good candidate for endoscopic resection. But we recognize that there is some small focus of relatively wide vascular area with elongated non-loop irregular vascular network, which are suggesting submucosal invasion. Therefore, although majority of this region consisted of loop-formed capillary network, only this area is suggesting submucosal invasion. And of course, after spraying iodine solution, it turns to unstained area. This is also typical appearance of skeletal cell cancer in the esophagus. And our prior operative diagnosis was skeletal cell cancer with submucosal invasion. Therefore, we recommended surgical resection or chemoradiotherapy for this patient. But because this patient was relatively young, therefore, this patient requested endoscopic resection to get the final histology before undergoing invasive surgical treatment. Therefore, we conducted ESD as a diagnostic purpose. But actually, it was invasive cancer, more than 200 micron. It was actually 700 micron submucosal invasive cancer with lymph vascular infiltration. And finally, this patient underwent surgery. And actually, this patient had the lymph node metastasis. Therefore, it was right decision to send this patient to surgery. In this way, how we can easily detect this skeletal cell cancer by typical appearance of the surface pattern and the also color difference and eye magnification is very useful for further evaluation. And of course, iodine staining is always necessary before conducting actual treatment. Regarding the Barrett's esophagus in Asian country, it is still very rare and the majority are short segment Barrett's esophagus and cancerous components are usually arising from the light side area. And it usually looks reddish area and half of those region looks like elevated lesion. And majority of the suspicious area can be easily detected by white light imaging. And if there is a big polyploid lesion or mixed type with polyploid and depressed lesion or tumor size more than 15 millimeter or remarkable redness on even surface or some epithelial extension to the esophageal side, those kind of findings usually suggest invasive cancer. Therefore, we should carefully check the suspicious area using white light image first. Then we should check the detail using NVI and magnification. And superficial cancer is also very good candidate for endoscopic resection for any size up to T1a LPM. But we recognize that the risk for lymph node metastasis is relatively low even for the superficial subcausal invasive cancer. Therefore, after complete resection of the target lesion, we can say that the treatment was curative. If the lesion size is less than three centimeter and the invasion depth is up to 500 micrometer, if there is no component for poorly differentiated adenocarcinoma, and of course, if the vertical and lateral margin was negative. This is typical case of Barrett's cancer located at the G-junction. You can see irregular reddish mucosa here. And by using NVI and magnification, we can see the clear demarcation line and the destroyed surface structure here. And we conducted chromoendoscopy. And surprisingly, this lesion was widely extending to the gastric caudia. Therefore, we conducted ESD to achieve curative resection. and it was nicely removed. And although the lesion size was quite big, nearly six centimeters in the greatest diameter, we achieved the curative resection. Preoperative assessment is quite important, even for the Barrett's esophagus. And of course, we should pick up the suspicious area using white light first. Then, after detecting some suspicious lesion, we should use image-enhanced endoscopy with magnification and chromoendoscopy for further evaluation of the target lesion. In the stomach, again, we should learn typical appearance of superficial cancer, such as irregularity of the mucosa or discoloration of the mucosa. This is one of the examples of the typical appearance of the early stage cancer. Shallow depressed lesion, which is compatible to zealotus lesion, is the most typical appearance of early gastric cancer. And also, 2A lesion, slight elevation, is also typical appearance of superficial gastric cancer. And discoloration of the mucosa also suggesting presence of superficial cancer when the lesion presents extensive redness or whitish mucosa. Usually, this kind of whitish mucosa suggesting poorly differentiated or signatory cell carcinoma. Majority of the well-differentiated type of adenocarcinoma usually present normal or reddish mucosal surface and majority are protruded or depressed. But for the undifferentiated adenocarcinoma, it usually looks whitish and it is completely flat or depressed. This is typical appearance of undifferentiated type carcinoma. And one side of the gastric cancer are still undifferentiated adenocarcinoma. That's why we should take at least one biopsy before conducting actual endoscopic resection or surgery. But now, we have very nice modality, which is NBI magnification or BLI magnification. And there is a nice publication regarding MESDA-G. MESDA-G is magnifying endoscopy simple diagnostic algorithm for early gastric cancer. This is actually very simple. If we find some suspicious region, we just switch on NBI or BLI. And if there is demarcation line, it is really suspicious of cancerous component. Then we come close to the target and using magnification. And if there is irregular microvascular pattern or irregular microsurface pattern, it is actually a cancer. For this example, you can see the clear demarcation line here. And there is irregular microvascular pattern and irregular microsurface pattern. Therefore, we can say that this is gastric cancer without taking biopsy. So, this is very convenient when we conduct screening endoscopy, just switching on NBI and using magnification. We can easily understand that this is cancer. We don't have to wait the result of biopsy. Just using NBI and magnification or BLI and magnification is usually good enough. Well, is this peptic ulcer or gastric cancer? Can you recognize that this is benign or malignant? Probably it's a little bit difficult and probably every one of you take a few biopsy from this one. But using BLI, we can see clear demarcation line outside the ulceration, which suggests malignant mucosa. Then, if we can use magnification, we can easily recognize that this is apparent gastric cancer because of the irregular microvascular pattern and irregular microsurface pattern. Although we just using NBI magnification or BLI magnification without taking biopsy, we can say that this is already gastric cancer. Therefore, we usually use NBI magnification if we find some suspicious lesion and check the extent of the tumor. This is very flat lesion, but by using NBI magnification, we can easily understand the extension of the tumor and we can easily recognize the border of the target lesion by NBI magnification or BLI magnification. But promoendoscopy is also very useful. I prefer to use 1.5% acetic acid plus indigo carmine. Now you can see very flat lesion located at the lesser curvature of the upper gastric body, but still the demarcation line is unclear. But by spraying acetic acid and indigo carmine, we can easily understand the border of the target lesion. Therefore, still we are using this promoendoscopy just before starting actual ESD procedure in our institution. And for the evaluation of the tumor invasion, irregular surface suggesting deep submucosal invasion, but if it is necessary, we sometimes conduct EUS to confirm the real depth of tumor infiltration to the deep submucosal layer. Well, this is current indication of ESD for early gastric cancer. For the well-differentiated cancer confined with mucosa without ulceration, there is no limitation on size. And if the target lesion is undifferentiated type cancer, indication for endoscopic resection is up to two centimeters. I would like to show you some of the example of the early stage cancer. This is a slightly elevated lesion, which is classified type 02A. And it looks like benign, but by using NBI magnification, you can easily recognize the clear demarcation line and irregular vascular pattern and surface pattern. This is typical appearance of superficial cancer. And after promoendoscopy, neoplastic area becomes quite clear. Therefore, we decided to conduct the ESD to achieve curative resection. And actually, it was a mucosal cancer sized 18 by 16 millimeter. This is another example of early stage cancer. Probably you cannot see anything, but if we come close to the target lesion, you can easily find this reddish depressed area. This is typical appearance 02C lesion in the stomach. And taken biopsy from here, we build the signet ring cell carcinoma. So as I mentioned, even for the signet ring cell carcinoma, if the lesion confined within the mucosa and less than two centimeters, still we can conduct the ESD because risk for lymph node metastasis is relatively low. Therefore, we are planning to do ESD. But before that, we spray the indigo gamine. And we recognize the slight color change around the depressed area. Therefore, I sprayed acetic acid and indigo gamine again, and finally recognized that the tumor spread was much bigger than two centimeter. It already become nearly four centimeter superficial cancer with signet ring cell carcinoma. This is not candidate for endoscopic resection anymore. We should provide surgical treatment for this patient. This kind of careful observation is always very important before making a final decision. Well, this is summary for the early gastric cancer. Suspicious lesion should be detected by typical appearance using white light and image-enhanced endoscopy and magnification. Chroma endoscopy is quite useful for further evaluation. In the duodenum, there is no definite diagnostic criteria still now because low incidence of duodenal lesion. But we should understand the character of duodenal lesions depending on the phenotype of the duodenal lesion such as gastric phenotype or intestinal phenotype. Majority of the duodenal lesion and small benign lesion look like this, but sometimes we encounter really aggressive lesion like this. And unfortunately, biopsy is not reliable enough. And if we take biopsy, it usually cause lots of fibrosis which disturbs the following endoscopic resection. Therefore, we usually don't take any biopsy from the target lesion in the duodenum if we are planning to do endoscopic resection. Of course, it already become invasive cancer. We should take a biopsy before sending those patients to surgery. But if we are planning to do endoscopic resection, we should avoid taking biopsy. Just focusing on the surface structure and the presence of the wasp. Wasp is kind of the position of absorbed lipid within the epithelial layer. And if the wasp is diffusely positive, these are mostly intestinal type duodenal lesion having lower malignant potential. But if the wasp is completely negative, it usually have higher malignant potential. And if the surface structure is completely circular, it also suggests the higher malignant potential. And it usually turns to gastric phenotype. And also, size of the target lesion is very important. And if the lesion size getting bigger, malignant potential also getting higher. And 30 millimeter is kind of cutoff ratio, which suggesting the higher malignant potential. Therefore, in case of finding suspicious lesion in duodenum, we have to check the lesion size, character of the lesion using NBRI magnification or BLI magnification. And lesion location, whether the lesion is upper side above the major papilla or below the major papilla, and whether the manoeuvrability is good or not. And we should carefully select the appropriate treatment method depending on the situation of the target lesion. Majority of the small lesion less than two centimeter can be easily removed by snare-based reception technique. But if the lesion size getting bigger, more than two centimeter, we usually perform ESD to achieve complete margin-free resection. This is one of such a case. This lesion was located at the second part of the duodenum, just adjacent to the major papilla. And when we checked the lesion using NBRI magnification, there was no loss, suggesting higher malignant potential. That's why we decided to perform ESD, although it was located very close to the major papilla. Therefore, we carefully cut just beside the major papilla, preserving the papilla itself and completely remove the target lesion. And of course, we should completely suture the mucosal defect to avoid serious delayed complications, such as severe bleeding or delayed perforation. And fortunately, this was just a mucosal cancer without re-vascular infiltration. Therefore, we achieved curative resection in this particular case. And this is another example of duodenal lesion, which was located at the duodenum valve, which lesion size was less than one centimeter. Although the lesion size was quite small, there was no loss, and the surface structure becomes a little bit irregular on the top of the protrusion, and it looks like submucosal tumor. That's why we conducted EUS. And as you can see here now, the submucosal layer completely destroyed and the proper muscle layer sickened. That means there is some risk of deep infiltration, even to the proper muscle layer. Therefore, we didn't touch this tumor and quickly send this patient to surgery. And surprisingly, this was already T2 tumor, although the lesion size was just eight millimeter in the greatest diameter. This kind of situation happens for the gastric phenotype duodenal lesion. Therefore, we should carefully check the target lesion before making final decision. Well, this is summary for the duodenal lesion. Suspicious lesion should be detected by white bright and size and presents us a very good predictor for malignant potential of the target lesion, and usually gastric phenotype has a higher malignant potential than the intestinal phenotype. Well, thank you very much for your kind attention. Professor Yahagi, thank you so much for the amazing presentation. It's really wow. It's an amazing presentation. And we have some questions from the attendees. And let's start with the first question from an expert. I'm really happy that he's joining. And he's asking about, is there any diagnostic or staging advantage of the new modes like TX, TXI, one or two, or even LCI in the esophagus, stomach or duodenum? So what do you think? I think TXI and LCI are very good for detection of the suspicious area because they enhances the color tone and also surface structure. But for the evaluation, I believe still NBI or BLI magnification is much better because we can easily recognize the irregularity of vascular network and the irregularity of the surface structure. Therefore, in my own clinical practice, I only use LCI and TXI for detection of the suspicious area. Then after having some suspicious area, I quickly switch to NBI magnification or BLI magnification. Okay. So the second question is also from our expert. It's Dr. Fatih Aslan. And I'm so happy that he's joining. His question is really a bit complicated about the undifferentiated cancers. They often invade the lamina propria and may involve a wider area than what is endoscopically visible. Moreover, these patients could be younger or tend to be younger than those of the differentiated top cancers. So in such cases, is endoscopic resection associated with a higher risk of recurrence? And is the lesion size still sufficient for the decision making or should additional staging be considered? I think that four-point biopsy, especially for the gastric undifferentiated type cancer is necessary and carefully check the lesion size. Although it is invisible, sometimes taken biopsy from around the suspicious area also turns to be cancer. Then it turns out to be much bigger than we expected. Then it is not a candidate for endoscopic resection anymore because of the higher risk for lymph node metastasis. We carefully check the lesion size and the invasion depths, although estimation of invasion depths for the poorly differentiated or undifferentiated type cancer is sometimes very difficult, but we carefully check at least for the size of the target lesion. So another question from one of the attendees, any tips to differentiate the Brunner gland adenoma from the regular adenoma and the duodenum? It's quite sometimes challenging, but the Brunner's gland adenoma looks like a big polyploidal lesion and it has relatively stiff bulky mass. Then we usually take several biopsy from the top of the protolusion. Then we can easily diagnose as it is a Brunner's gland adenoma. But for the Brunner's gland hyperplasia, we cannot get any histological result showing adenomatous component. But we sometimes conduct EUS, the epithelial structure becomes quite irregular or not. If it turns to quite irregular, we sometimes conduct diagnostic endoscopic resection to check the entire histology. Okay, so another question from the audience about Barrett's oesophagus. They are asking about the blue dye used for chromoendoscopy. So we want to know the type of the dye. Probably due to the lack of indigo coming in the Western world. Unfortunately, I don't have any experience to use Mediterranean blue or other blue dye, we only use indigo in our country. Therefore, I have no idea, but probably you can spray methylene blue on the surface of the Eagram because then you can enhance the surface structure, at least it will be helpful to characterize the target region a little bit more. But I prefer to use acetic acid before spraying blue dyes because we can tentatively fix the surface structure, then we can more easily recognize the difference of the surface structure after spraying 1% acetic acid and washing away sticky mucus using normal saline irrigation. So any concentration for the acetic acid that you use? Less than 1%, that is good enough in the barrette esophagus, 1%. Yeah, so Professor Yagi, I'm asking a very simple and basic question because in my country, in the region, we don't use the chromoendoscopy, we just use the virtual chromoendoscopy, the neural band imaging, the BLI and stuff like this. And I think that you're still insisting on using the chromoendoscopy and we watched just some amazing cases. And I have noticed that the chromoendoscopy was really helpful in the size of the lesion, in the borders. This is maybe the edge on the data, not the depth of invasion, right? Yeah, that's right. You are right. For characterization of the target lesion, BLI or NBI magnification is usually good enough. But for the demarcation of the target lesion, sometimes chromoendoscopy is much better than NBI or BLI. That's why still I prefer to use chromoendoscopy just before conducting ESD to have clear demarcation line of the target lesion. That's our usual strategy. And even for the esophageal skeletal cancer, we always spray Lugol's solution just before conducting endoscopic resection. It's mandatory step for us. So thank you a lot for the amazing presentation. Thank you very much. We have many questions that seems everybody's attending and they are attentive also. So let's move to our next expert, Professor Altman from USA speaking about the lower GI lesions. Please, everyone stays with us. Just a disclaimer here that the last four chronic question that everybody answered 25, 40% were my question. I felt very terrible at the end. I felt like I put very hard questions. So I hope after this lecture, you guys will answer this question again. And I think Shayma will put the question back to us and then we'll be able to see if you can answer them better. But I was glad though that some of you got it right. Okay, we'll start with this first slide. I love this slide. This is from the Multi-Society Task Force published in 2020 by Tania Kaltenbach. It's a beautiful paper. If you never read it, please read it. It is one of the most beautiful one done for colon polyp characterization. Paris classification is the most important classification for polyps in the colon. The reason is it doesn't require a lot of advanced imaging. It doesn't require magnification. It does not require dye, and you can teach it to everyone. So I will stress a little bit about this classification here. Anything that's raised, it will be 0-1 or type Paris 0-1, as you can see here, like the truncated and societal polyp. So your most common polyps that you see in everyday practice when we classify them by Paris classification, it is 0.1. And then managing them depend after that on the size of the lesion. Obviously, truncated one, you can snare them. Societal one called EMR, or we can do even hot EMR for larger than two centimeter. But not all the lesion will be nice like these ones. You can get other lesions that are flat. And when we talk about flat lesions, you have to think about flat as slightly flat, elevated a little bit, or completely flat, or flat with slightly depression. And this is called type 2 lesion. So type 2 lesions are flat, and as a slightly elevated, they are 2A. Truly flat is 2B, mildly depressed is 2C. You can see here in the image, there is difference between societal polyp and this one here that's slightly elevated. So what we are looking at here is a Paris 2A polyp. This is not societal. Some people call it societal. I call it 2A. And then you will get depressed lesion, and they're deeply depressed, ulcerated. We used to call it hip amicosa. Looks like the top of the volcano. You look at the polyp, and you found a depressed area. This is cancer. How many times I get referral just for ESD with these lesions? A lot. I would remind you, the depressed lesion, like the one you see in this picture here, which is type 3 extubated or TC, this one would go for surgery. It should not be done by endoscopy. All right, so excuse my drawing here because I drew this slide for you to differentiate two things. Real depressed and ulcerated lesion, as the one you see here. This would be a 2C ulcerated lesion, and sometimes they have an elevated area. It is 2C, 2A. But then sometimes you will have a raised polyp with a depressed area within the raised polyp. That's actually 2A slash 2C, flat elevated lesion, slightly central depression. Okay, I don't want to confuse you so much, so I'm going to show you a video of a lesion right now, and we're seeing it here. You can see the lesion is slightly raised, but you have a small central depression. If we look at the classification right now, if this like depressed lesion was elevated, deep submucosa or the other way around, actually, this is a flat lesion with a slight depression. The majority of the lesion is flat with early depression. So why I'm stressing this differentiation now? Because this is how we determine what will go for ESD or not. This lesion had an ESD. It ended up being high-grade dysplasia. By Japanese criteria, they call it intramucosal adenoparcinoma. But it is not having deep submucosa invasion. If that was a depressed lesion like the image we saw here, and this one, in image three here, this one is for sure cancer. So able to differentiate between slightly depressed lesion and fully depressed that's really cancer is important. And we can see here that there's a study looking at lymph node metastasis based on virus classification. This is a very old study, and this was based on how we decided that this type C or any depressed lesion, they should not go for endoscopic resection because 61% of these lesion have lymph node metastasis. Okay, now we spoke about, you look at the lesion and you say, is it elevated? Is it flat? Is it depressed? I will introduce now a new concept. That concept, I love to hear it more and more from our endoscopists, particularly the trainee, which is LST, granular versus non-granular, lateral spreading polyp. Okay, so if you think about the polyps as two types, there's the type that is bedonculated and have a trunk. This is almost like the tree in your garden. We call them bedonculated polyps. But also in the garden, you can grow the weeds. And what happened to the weeds? The weeds don't go up. The weeds go to the surrounding area and fill your garden. And if you don't take care of it, they might take the entire garden. That's what we call them lateral spreading. So LST is lateral spreading tumor. And lateral spreading tumor can be with granules and can be without granules. The most common place you will see them is in the rectum, but you see them also on the right side of the colon. When you see them, you have to recognize them and you have to describe them as they should be described by this classification. So in the picture A here, we have a granular polyp. And the picture B also have a granular polyp. And in C, we have a granular or non-granular polyp, as you can see here. And sometimes we'll have mix of flat, smooth area like that with nodule next to it. And this was one of the question. You had an entire lesion that was flat, was one polyp, one granular area. That's what we call mixed granular. All right. We look here at the number D is what? Ulcerated lesion, early cancer. You cannot do, if you do ESD here, you might have deep tumor submucosa invasion beyond the one third. And you might need to send the patient for surgery. Some people will do ESD for this, but traditional teaching, that will be cancer. You shouldn't touch it. So for number A, this, we see it a lot. This granular LST, we see them all the time. This is the fight, fight between whom? Between the people in United States who are saying, do EMR for this versus do an ESD. And why is that? Because the risk of submucosa invasion in this lesion is very low. It's less than 3.2% risk of submucosa invasion. So it makes sense to remove this lesion with piecemeal EMR. I'll fight that, some guidelines will say, you can do ESD in them and we're gonna discuss it later on. But when it comes to non-granular lesion, like the one you see in C, well, this is a 15% submucosa invasion. If you see something is smooth and laterally spreading like that, it is perfect for ESD because the risk of submucosa invasion is very high. So now we know granular versus non-granular. I would like also to introduce another concept. Sometimes these granules could be almost the same size and sometimes they'll be heterogeneous, not homogeneous. You'll have like one large nodule. So if we look at this picture right now, I will call this granular LSD. This is the best description for it. All right, so what are the feature, like the feature of submucosa invasion in granular tumor? If you have very large nodule, one larger than 10 millimeter, or if you have non-granular larger than two centimeter. All right, so now we finished an optical inspection with a regular light, and we'll talk about narrowband imaging. Narrowband imaging using a special light to identify the lesion. This was the first classification that came called NICE classification. A NICE classification, the aim from it was just to make it easier for you to know the hyperplastic from adenoma from cancer. So basically, if you look at the image here, what we call type one, you will find it hyperplastic polyps. And why? Because it has this white spots in the middle. You'll notice there are white spots everywhere. Type two is adenomatous polyp. Remember the sulci and gyri of the brain. This are tubular structure, and the tubular structure here looks like organized. Yes, there is thick blood vessel, but it's not that bad. That will be adenomatous polyp. Now in type three submucosa invasion, you can see that there is no sulci and gyri anymore. You can see the middle start to become amorphous, which means like have no characteristic. And then you're gonna see too that the lesion is starting to get depressed. So what you are getting here, more and more depressed lesion, depressed lesion. That's what we worry about all the time. So why we don't use this classification all the time? The problem was NICE classification is that it omit a stage. From type two adenomatous polyp to type three submucosa invasion, which is the stage that is not yet cancer, but almost cancer. And these nodules, these like tubules that you see here, start to become irregular. That's why Japan NIRVAN imaging expert team came up with a new classification. It is almost like NICE classification with the exception of adding this in-between stage that we could not find before. So if we talk about type one in GNET, it is almost like type one in NICE. You're gonna find this beautiful, regular dark and white spots. When you see that these are hyperplastic polyp in the left side of the colon, if you see them in right side of the colon, most likely sessile serrated adenoma, depending on location. And also sessile serrated adenoma will have a different characteristic in a way that sometimes it has this blood vessel, star-shaped blood vessel, and we'll show that a mucous bag. Now, type 2a is the same like the NICE classification, type two. If the sulcangui rise of the brain, NICE tubular structure, regular caliber, regular distribution, it always have few shapes, either tubular or papillary. And most of the time, this is low-grade dysplasia or what your pathologist will call the United States tubular adenoma. All right, before you go to cancer, this tubular start to open, become wider, the blood vessel, and instead of being nice and cute and small, they start to become interrupted and thick and irregular, and that's type 2b. This is what is different about the GNAT classification. In addition, it's type 2b, when you have a variable caliber blood vessel, a regular obsecure, that's a high-grade intramucosal neoplasia, it could be even early cancer. If you see this, do not do EMR, this one you need to do ESD. So the GNAT classification allowed us, all of us right now, to use your magnification on your endoscope and look closer to the lesion, and you will decide for sure which lesion now we'll have to do ESD on. So type 2b, we advocate for ESD. Type 3 in GNAT, the same like type 3, a NICE classification, amorphous lesion, no visible area, and this one you have deep submucosal invasion. So sometimes differentiating type 2b from type 3 could be hard because you can see some of these lesions similar to each other. So now we're gonna get an example here of a lesion on the right side of the colon. We're gonna switch to NVI and then near focus. In near focus, you have to get closer to the lesion, stabilize your cab, and start looking at what you're seeing here. We can see that it's actually, in my opinion, this is GNAT 2a because everything is still regular and NICE is not yet 2b. You don't see the blood vessel getting irregular. So what about this lesion? This actually, if you look at it, does not fit in with any classification over there. This is a hyperplastic bulb. You can say GNAT a. And if you look at this lesion, the physician who referred it, who removed most of the lesion first, and then he could not notice that sessile serrated adenoma can spread behind the fold. So you're gonna find the scar at the beginning of the lesion and the rest behind the fold of sessile serrated adenoma. If you inject this lesion, you can always see the extent of them. A word of advice, and you see sessile serrated adenoma, be careful. A lot of the time, this lesion are extensive and they might be larger than what you think. And sometime before you empark and removing them, just inject under them to see how they look like. In this video here, we're using SP knife. It is good for the beginner to use this knife because it's allowing you to do ESD safely. All right, so now we're gonna talk about another classification, which is not endoscopic classification, but it is a pathological classification. And it is for one of the polyps you see all the time, pedunculated polyps. So pedunculated polyps, we tend to remove them by EMR, but sometimes I prefer ESD if you see changes in the surface like adenocarcinoma, because if the adenocarcinoma go all the way deep to level three, as we can see here in the stack, or even level four, and you see this a lot, that the lesion is removed, and then the pathologists say that there's adenocarcinoma in the stack or going to the submucosa. For that reason, you know, we have to examine even this polyp on the surface very well. If you suspect any submucosa invasion, either you put your snare as deep in the stack as you can, or sometime I do ESD of the stack to ensure I'm going as deep as I can, so that you can have accurate determination. You can see here, risk of submucosa invasion increase as deep the tumor go into submucosa, and the colonic lesion is 2%. If you are the upper third of submucosa, 9% in the middle third, and 35% in the lower third. So how we calculate that here? You have to think about it that it is up to 1,000 micromillimeter, what's considered the SM1 in the colon, and for non-bedoncated lesion. Remember when we do endoscopy, we don't really remove the entire submucosa as surgery. This classification of SM1, 2, and 3, basically you're doing full thickness, but when you do endoscopy, you count the depths from the end of the mucosa to the end of your specimen. And that's why if you are doing ESD and suspect there is cancer, try to go as deep as you can close to the muscle layer so that you can have enough submucosa for your pathologist to assess the depths of invasion correctly. So what are the predictor of lymph node metastasis once you remove the lesion? Now we remove the lesion after you assess it, you thought it is good, it can be done by ESD, but then you find one of these features and this patient still has to go for surgery. If they have lymphovascular invasion, if they have deep submucosa invasion, if they have poorly differentiated element, mucinous adenocarcinoma, and there's something called tumor budding and we're seeing more and more of it to suggest lymph node metastasis. So that's your characteristic. If you've seen your pathology report, one or two of these, this patient might need to go for surgery. There's argument now, there's new evidence saying that maybe one criteria, you can watch this patient. But if you have two or three of these criteria, I would be worried not to do surgery for this patient after ESD. So here are examples of lesions that you can remove by endoscopy for ESD. So lateral spreading non-granular. So what we see here, this is a bulky non-granular lesion, and bulky like that, non-granular started to be amorphous, this was early adenocarcinoma. This is recurrent lesion, this is granular lateral spreading polyp, and then in ulcerative colitis, you can find some lesion with dysplasia, and also remove them. All of these are example of chronic ESD lesion. So that's here an example of granular lateral spreading lesion. And I actually included this one to show the technique of ESD using the bridge technique as a courtesy to Dr. Shayma Al-Houli, who introduced me to that technique, which you start from the oral side of the lesion to the anal side of the lesion, leave the sides and create this nice bridge in between. And once you create the bridge, you can dissect the lesion. So just added, this is how we do ESD. And this was a granular lateral spreading polyp. This came back as tubular adenoma. This is a type of the lesion that in the United States, you can just remove with EMR with no problem. But if ESD can take you 30 minutes to do it, you can just do it too. It's not a problem. So this is an example of another lesion, recurrent lesion in the colon. You can see here is just tubular adenoma, but it was removed three times. So this time we're doing ESD. And why I'm including this slide? Because of the ink. People ink under the lesion is still in the United States. We're using bipolar knife because of our decreasing amount of energy. But can you see the muscle layer and how the ink is there? So ink migrate, and remember to tell your referring physician to put the ink, not opposite side of the lesion because it will migrate down, but two to three folds away from the lesion. We're using the bipolar energy here to dissect in the ink fibrose area and to limit the amount of energy we deliver to have a clean dissection. All right, we'll go back now to the U.S. Multi-Society Task Force and to review when we evaluate the lesion. If it is non-invasive and small, 10 to 19 millimeter, you do cold or hot SNARE propectomy. If it's larger than two centimeters, you do EMR. If you suspect submucosal invasion and this submucosal invasion is minimal or moderate, you should do ESD. We don't have guidelines yet in the United States saying you should do ESD. So that would say, what we'd say here, EMR ESD of complete resection is feasible and safe. It's based on the lack of expertise of doing ESD in the United States in the colon. That will change very soon with the new guidelines from ASGE. If you suspect deep submucosal invasion, then you refer the patient for surgical resection and you get biopsies from the suspicious area. So what about the ASGE, European Society of Gastrointestinal Endoscopy? They do have an indication for ESD for depressed morphology lesion in the colon, a regular non-granular surface pattern, and if the particular lesion larger than 20 millimeter. They published these guidelines in 2015. However, in 2024, they came up with this interesting recommendation. They said ESD may also be suggested as an alternative for removal of large non-bulboid colonic polyp of more than two centimeter in size in selected cases and high volume center, i.e. if you are good in doing ESD, you can do it for granular lateral splitting larger than two centimeter. However, this is weak recommendation with low quality evidence, but they are trying to say it is okay to remove larger GLSD because some people from the other side will say, while you do even ESD for this, you must do EMR. What about Japanese criteria for indication in ESD in the colon? An M-block resection is not fully feasible as EMR. That's the number one criteria. If you can do M-block resection, do ESD. For LSD, non-granular. KODU type 5 pattern, we did not talk about KODU classification, but that's a primal endoscopy that Dr. Yahagi showed us a beautiful picture of. In the United States, we don't use it as often unless we have an IBD patient, but if you have KODU type 4 or 5, KODU type 4 patient, you can do it. Shallow SNN vision, large depressed type tumor, large protruded lesion, mucosal tumor with submucosal fibrosis. This in the United States, we call it recurrent lesions. Lesions who are coming back after EMR and failed EMR or recurrent after EMR. And also, sprouted localized tumor in case of chronic inflammation such as UC. It is better in UC to do ESD, and I do that in my practice too. Local residual recurrent early carcinoma after endoscopic resection. I feel like the Japanese criteria is the most comprehensive, most detailed. I hope in the United States, we'll be able to apply this criteria one day, and it's almost there, and I think it will be also everywhere else in the world. So before I finish, I will leave you with this algorithm. So you have a colorectal lesion, start to think about bedonculated versus non-bedonculated. If it is bedonculated and you have an N-block resection, that's great. Benign, you have surveillance. If you have submucosal cancer and the target classification is deeper, then you go for surgery. Now, if you are non-bedonculated, you're going to use your GNAT. If your GNAT is 3 or KODU type 5, then you go for surgery. If it is GNAT 1 or 2, and you think about is it granular versus non-granular. We've talked about the non-granular, it's a smooth one. This one has a higher risk for surgery. So if they are societal depressed or ulcerated, consider N-block resection by ESD. If they are flat, you might consider EMR or ESD, but if they are granular, if they have a large nodule, we said the larger nodule by itself is a reason for you to have cancer, particularly in the rectum, then you go for N-block resection. If it is homogeneous with no dominant nodule, you might go for EMR versus ESD, depending on what you see. Thank you so much, and this will be the end of my presentation. Thank you so much, Professor Altman, for the very clear and to the point presentation. I really like that, and we have some questions. So a question from one of the attendees, they are asking about the name of the knife that you stated is good for beginners in ESD. It's called SP knife. It's almost like there's another version of it called clutch cutter 2 from Fuji, SP knife from Olympus, and basically these knives allow you to hold the area that you want to dissect and then dissect it. It slows you down. Sometimes people use it after they do initial incision, but you can do the initial incision with it. I find it good for trainees, but sometimes there's issue with it too. You have to be careful with that because sometimes if you take a lot of tissue, the tissue can get stuck to the needle, so you have to frequently clean it. One of the advantages is that you will only cut what you hold, so you will decrease risk of perforation, and the other advantage is that you really can hold something and you don't like it and open back without cutting and choose another area. So for beginner, it is something safer. Yes. Another question that I was going to ask myself, and it's also from our expert here, he's asking about Kudo classification, because as you said here, the Paris, the JNET, which is really important, is the Kudo classification, the question, is essential in the pre-assessment? This is the first one. The second is the virtual chromoendoscopy or even the standard indigo carmine sufficient for this classification, or we should add crystal violet? So Kudo classification was created for chromoendoscopy. Some people would use it for virtual chromoendoscopy. That's actually not correct. It is created for yohonyoboda dye, and the dye reacts with the tissue. So we really worry a little bit about like methylene blue, sometimes if you spread it around the lesion, it becomes very hard to suction it, affect the lens, and sometimes it lingers around the tissue, and especially if you work in the colon, it's unlike upper, the stomach is different situation. Lesions are subtle, and using chromoendoscopy, like the actual chromoendoscopy in the stomach, is extremely helpful, because you can see this early subtle lesion. The granular polyp in the colon, usually they are obvious. In fact, when people do resection, they might not even put points or put like marks and marks a lesion, because it's very obvious in the colon. That's completely different when you're dealing with the stomach. So I feel like the actual chromoendoscopy might be very important for gastric lesion. Before I do any gastric lesion, I use chromoendoscopy, but in the colon, I rarely use it, unless it is IBD case or something. So I don't consider it essential for chronic ESD evaluation. So we have from Dr. Kondal, I think he wants to add a comment or a question. Yeah, just a quick comment and also maybe a question. Thanks to both of you. I mean, these are amazing lectures, outstanding, and kind of took me back to my advanced endoscopy training days. And, you know, thank you again. It was really useful, and I'm sure the audience enjoyed it. And Shaima's moderation was excellent. Just a very practical question. It's not directly related to lesion recognition. I apologize for that. But Uthman, Mohammed, you know, you're in the U.S. and you are aware of the challenges we face with kind of CPT codes and billing and time allotted for these ESD type procedures and such. Very briefly, without taking up too much time, I'm sure there's others who want to talk about the topic at hand. How do you manage that? And how do you allot time? For example, if someone's interested in learning it, how do you organize billing? Do you negotiate with insurance companies, things like that, to compensate and cover for these very important procedures we do, ultimately, to make our patients better in a minimally invasive way? How do you navigate that? Yeah, so it's hard. If you go to Japan, they have a nice national health care system, and the ESD is actually a good, nice procedure. And the system will filter the cases to the large centers. So if you go to Professor Yahagi, you can see three or four rooms running ESD at the same time. You know, his room and his partner's, and you can watch all the procedure all day. It's amazing. In the United States, it is sporadic and is also fragmented. And the reason is lack of coding. So this will change very soon. 2027, we expect to have a code. Actually, I might announce this right now that there's a group of people, including industry, Boston Scientific and Dr. Brian Duncan, applied for the code on behalf of a group of Medtronic, Boston Scientific, and with the support of ASGE and support of AGA and ACG for a code. We're going to hear the results very soon, at any day. So we might have a code in 2027. So that's good news. The other thing is, for now, until 2027, you have two options. You can use EMR code and you use modifier 2022. And modifier 2022 means that you are saying, I spent a lot of time doing this procedure. You have to document why you needed long time, and you have to document the amount of time you spent. I spent 120 minutes. So this will take you from EMR code, which is seven, you became like, you can ask up to nine reviews. It's still- That's what we're doing now in our practice. We- I don't do that though. I can't do that because if I do that, I really will not generate my salary. So I do a different process. I use unlisted code, which is not even EMR. And what I use is I do a process called predetermination. It's not a pre-authorization. Pre-authorization means, please allow me to do the procedure. Predetermination is a one month process that you ask the insurance voluntarily to evaluate this case and determine that they're going to pay for it. And if they don't- You designate the reviews for that? And you, yeah, you send a letter saying why this is important. And then you argue how much you want. And we agreed to get three times of what we do for EMR. So in my institution, we looked, and I published that for physician payment. We looked at how much you get paid in general from commercial insurance if you do ESD. And it's equivalent of 14 hour views for colon ESD and 12 hour views for each EMR. And this is how right now we are paying our physician who does ESD. In my group, we have four people doing ESD. And we do- So you've gotten good cooperation from the insurance companies? Initially, it was hard. Now they know about it. But not only that, you will get rejections. And if I get rejection, I don't do the case or convert it to EMR. Because if I only do cases and hope to get paid, I may not get paid. So we have this process of predetermination. And I explained it in my publication before, but it is the best process for now. But very soon, once we have the code, all of these problem would be out. There's one extra thing called a C code the hospital can add. If you do ESD, the hospital have an additional C code that pay the hospital, not the doctor, $2,000. That can cover the cost of the knife and other things. So the hospitals are not losing now ESD because they can all use the CD code for their colonic ESD. Unfortunately, it's not available for upper yet. Again, I apologize for kind of distracting, but I think this is important for a lot of the U.S. audience to understand. Yes, yes, exactly. So Professor Altman, before we go to the to the quizzes, because we're running out of time, I have a question for you regarding the JNAT classification. There is always a sentence that is written about the JNAT2B. There is like an asterisk and it's written that deep submucosal invasion could be included. I want to know your comments about this because some people... And JNAT type 2, right? Yeah, JNAT type 2B. Yeah. And this is my first question. Yeah. My second is there are some borderline cases where you're not sure is it SM1, SM2 or SM3, but you're sure it's not T2. But what do you do for these cases? Do you do like an ESD like as a diagnostic thing to to verify or what do you do in such borderline cases? So for the JNAT type 2B, it is almost a lesion going to become cancer. So when you remove it by endoscopy, you also have to think that you might be surprised, you know, like like Professor Yahaji just with a lesion, adenocarcinoma and that wadnum, it came back. I thought and I thought this would be a very superficial adenoma. It came back as a T2. So also there's still some limitation of visual inspection. So that's why anything that JNAT type 2B, you might be surprised that you're going to have cancer and we have to accept that risk that that's a limitation of any classification we have. Maybe it was endoscopy and TXI. We don't have data about this yet in the United States, but maybe you can have better classification once we have these new models. But for now, JNAT type 2B have a limitation that it can be early cancer and new message. And the second question was borderline cases. In borderline cases, depending on the patient age, depend also on the large lesion. If the lesion is too large, and I learned like that from our management of very large lesions, are the ones who can have both plepectomy syndrome and post resection syndrome. The worst thing ever you do is to expose the patient for a huge, like three, four hours procedure, end up needing to go for a surgery and they get adverse event after it. So if it is three centimeter, four centimeter borderline, I'm not sure if it's T1 or T2, yeah, I can do a resection and close it. If it is extending over threefold, and I'm really suspicious, and the patient have comorbidity that they might even get sick from being under anesthesia for a long time, it might be better for them to go for right hemiplegia. And as an endoscopist too, we have to start to learn when to stop, where to stop and what's our limitation. One of the lesson I learned the hard way, people can have adverse event, not from your procedure, but from being under anesthesia for a long time. So we are going back to our quiz questions and at the end of the quiz questions, I'll ask our panelists, Professor Yahagi and Professor Othman and Professor Kaina to give us an advice about how to improve our lesion characterization. So please don't go. So we will go again with our quiz and now we will have Professor Yahagi also with us to comment. Can you please answer this? This is a 68-year-old patient and we found this lesion. Can you please re-answer again to see if there are... So what do you think for this lesion? Is it biopsy, Lugol's iodine, MBI or CT scan? So it's MBI. So Professor Yahagi, your comment. Yes. Of course, Lugol's staining is very helpful to delineate a clear border, but it is necessary to characterize the target lesion, especially for the invasion depths of the tumor. Therefore, MBI magnification is much important than Lugol's staining to evaluate the target lesion before conducting endoscopic resection. We usually use Lugol's staining just before conducting endoscopic resection, but for the characterization of the target lesion, MBI magnification is quite effective. As I have already shown you, Japan Espagillo Society's classification of IPCA pattern is quite helpful to estimate the lesion depths just observing the IPCA pattern and vascular area. That's why we always use MBI magnification after finding some suspicious lesion. And if it turns to superficial cancer, which is a very good candidate for endoscopic resection, we schedule it for EMR or ESD, then spray Lugol's staining. Of course, CT scan is essential to rule out potential lymph node metastasis. Therefore, before conducting actual resection, we also conduct a CT scan. But first step is always MBI magnification, then make a strategy. And if we are planning to do endoscopic resection, we spray Lugol's solution just before endoscopic resection. That is my answer. Yeah, thank you so much. This is now very clear. So, but we are having much improvement in the results. So, this lesion in the stomach, I think you show it in the presentation. This lesion is indicated with a white iris and it's around two centimeters. And the biopsy shows it's a signatory carcinoma. So, what do you think, to do chromoendoscopy first or go straight away with EMR, ESD, or laparoscopic surgery? I think it is necessary to determine the extension of that tumor along the depressed area. That's why we usually conduct chromoendoscopy to determine the actual tumor extension. And if there is no suspicious area having tumor extension outside the depressed area, still we take a four-point biopsy outside the depressed area. Because sometimes signatory carcinoma extending below the healthy surrounding tissue. That's why we usually take a four-point biopsy around the depressed area. Then if all the taken biopsy revealed negative for cancer, we can do ESD. Because this is a superficial cancer confined within the mucosal layer and less than two centimeters, it's also a good candidate for ESD. But if one of the taken biopsy positive for the signatory carcinoma, that means it already become more than two centimeters in size, then it is a surgical candidate. And of course, chromoendoscopy already can give us some additional comment that the lesion already extending outside the depressed area. Actually, in this case, I already showed the nice chromoendoscopy which showed a relatively wide lateral extension that was very useful to recognize the actual size of the target lesion. So our step is using chromoendoscopy first, then take a four-point biopsy, then make a final decision. That's my answer. Professor Yahagi, I would like to take this chance to ask you a question about the signatory. Because we all know that the behavior of signatory is really aggressive. And I have this experience with a patient, rectal ESD, and he was an SM1 with signatory cancer. And this was my first time to see an SM1 with a positive lymphovascular emboli. And I sent this patient to surgery because of this lymphovascular emboli, sorry, rectal sigmoid. And then after the resection of this, the patient also had recurrent lesion. So I had this kind of, ah, it was traumatized with this behavior of the signet ring cancer. So it's still applicable the same rules for the adenocarcinoma and the signet ring, upper and lower GI? I think it's completely different. I literally see the poorly differentiated or undifferentiated type cancer in the colon and the rectum. I think the character of the poorly differentiated adenocarcinoma in the colon is much more aggressive than the upper GI adenocarcinoma. Because at least in the stomach, one side of the gastric cancer still poorly differentiated or undifferentiated adenocarcinoma. But if the lesion is confined within the mucosal layer and less than two centimeter, risk for lymph node metastasis is quite low, probably less than 1%. Therefore, it's quite a good candidate for endoscopic resection. But for the colonic lesion, I think it's the different scenario. What do you think about this, Dr. Altman? Altman, what do you think, Dr. Altman, about this? Yeah, I wanted, yeah. So in the United States, why 22% of the audience chose surgery? Because for us, a worse stigma crane means you have to go for surgery. However, people are not noticing something. In the United States, this lesion is not as early or not mucosal. Most of the time, they really have deep submucosal invasion. And that's why we have that. I think a lesion like that's extremely subtle. If you take it with a good wide margin around it, and most likely they do well, but we don't see this early, very early stigma crane in the United States, actually. And that's why there's a slight discrepancy here. Whatever we see is already slightly more advanced. So moving on with this nice lesion, also Dr. Yahagi, Professor Yahagi showed this in his presentation, this protrusion in the posterior wall of the bulb, and the biopsy revealed it's an adenocarcinoma. So, vapectomy, EMR, ESD, or surgery? Okay. Because it's hard to make a decision just looking at the white image, because there is no information about invasion depth by the white light image. But this is typical appearance of gastric type duodenal tumor, which usually have higher malignant potential. And it looks like already some epithelial tumor. That's why we usually conduct EUS and confirm the real invasion depths. Actually, when we conducted EUS on this particular patient, it already suggested the deep invasive cancer because proper muscle layer already sickened and the border becomes quite unclear. That's why we strongly suspected that this was really invasive cancer, even to the proper muscle layer. Therefore, we quickly send this patient to surgery without touching by ourselves. And actually it was T2 cancer in this case. So, this kind of algorithm is very important for us. If we find gastric phenotype duodenal tumor in the duodenal valve, even for the small sized lesion, we should carefully check it. Sometimes we should conduct EUS. And Professor Yahagi, I wanna say here that this type of lesion are really, I would say deceiving because it doesn't have any abnormal imaging. There's no amorphous layer, but what's really makes a difference here is not the morphology, but it is the phenotype, that this is a gastric type of, yeah, and that's why. That's right. Yeah. If this kind of lesion having opening, secreting the mucus, it's suggesting a kind of Brunner's grand derived tumor, then we can remove it by ESD, but there is no opening. And this is typical appearance of gastric type duodenal tumor. It's really a risky target. So, we should carefully check it. Thanks. So, going to Dr. Altman's questions. Now, we have this patient. What do you think about this lesion? This is an, is it a laterally spreading tumor, granular type? Is it mixed granular type? Is it Paris 1S, Paris 2C? Is it non-granular? So, you have to choose. I really ask all the participants, please, all of you vote. We still have a large number of participants till the end, and kindly, all of you vote, please. So, what do you think, Dr. Altman? Yes, I think it's true. This is, most of you got it right. That's a mix of granular, non-granular. Actually, the majority of this lesion is non-granular, as you can see here. However, you have one large nodule, which is granular part down there. So, that's a mixed tumor. It was a granular part and non-granular part. Interestingly, this one came back as tubulovilus adenoma, or it was high-grade dysplasia. So, it was almost cancer. So, wow, this is a very tricky lesion. Well, this 82-year-old male, presenting with iron deficiency anemia. This is on the sigmoid. Is it a sessile-serrated? And sessile-serrated lesion needs like a special webinar for them. Yes. And, yes, is it a word? Yes. Yes. Remember, Kondo, you should do one about sessile-serrated adenoma. Yes. It should be. Well-differentiated adenocarcinoma, tubulovilus adenoma, tubular adenoma, or just a hyperplastic bulb. Lady wants to have a nice image of NBI magnification in this particular case. Then, we can give the correct answer much easily. Yes. Very tricky from Dr. Altman. He's putting some challenges. Yes. I agree. It could have been easier if we just got closer and had a magnification. But there's certain clues here. It is adenocarcinoma. Yeah, and it's true. This actually came adenocarcinoma. Depth of invasion was 250 micromillis. So, barely adenocarcinoma. So, this lesion is actually, you would have say it is tubulovilus adenoma. Nobody would fault you. But there's a few things here. It's so bulky. And what we learn is bulky lesion, large in size like this, almost taking half of the lesion. It's not a granular blood vessel spreading in terms of this granular spreading. It is condensed in one area and it's becoming very thick and bulky. You can start seeing the regular blood vessel happening on the surface. And yes, we wish like if you go to the back here, you'll find an early depressed area there too. So, that was actually well differentiated adenocarcinoma. But I agree, we could have had a better image of this lesion. To make it easier. Yeah, but the lost vascular, I think the lost vascular pattern is seen. So, this is another tricky lesion from Dr. Oatman. This lesion was sent for ESD, but the site was not mentioned. Where was it? It's a type, it's a JNAT type one, JNAT type two A, JNAT type two B, JNAT type three, or we cannot classify this lesion using the JNAT. All right. And I would like to also take that, a professor to have your opinion on this, because this lesion is very tricky. It's almost as it has two things together. That component here, which almost looks like a gastric batter of high grade dysplasia. But then if you look in certain area, it is JNAT type two A, but you can start noticing that the blood vessel becoming thicker. Some of them becoming irregular. If you look at the lower image at the right side, you'll see that. If you look also at the upper image and look behind this part that looks like a mucous cap, you'll find a lot of irregular blood vessels too. And there is even another area that you have a loss of surface pattern completely. But Professor Yahagi, what do you think? So for this one, I classified it as JNAT type two B, but I would like to hear Professor Yahagi's opinion about that. I think it looks like a mixture of JNAT type one and the two A, and it looks like SSL. But I need to have more closer view with magnification. I'm sorry saying this. Yeah. It's actually, yeah. It actually came back. So the problem is it came back as tubular villus adenoma. So it came back as TVA. But I felt there's a component of sessile serrated to it. So this was an almost mixed lesion of tubular villus, I think was the sessile serrated. The part that it could be, but it came back majority of it was tubular adenoma actually. Tubular TVA actually. And, but it is abnormal actually here. So Professor Yahagi think it is JNAT type two A. I feel the image down there is type two A, the one which is in the bottom one. I feel part of the one up here is type two B in the image up there. So I feel it's a mixture of both, but I actually not a hundred percent sure. So I think Professor Yahagi think it is actually type one and two A. Yes. It looks like it's just, it looks like for me in the beginning, I saw that it's sessile serrated because even this lacy blood vessels on the right. Yeah. It's strange. Yes. But it came a combination of both. Tubular adenoma with SSA together, which is very interesting to find. It's almost a combined lesion. I have a beautiful video of it too. And this was a life endoscopy conference. And we were four of us in the life course, and we couldn't even classify it because it came back with different, it part looks like adenoma, part looks sessile serrated. And we end up saying it is mixed. It is a, it could be a case report actually. Yes. Yeah, yeah. It's very interesting case. So here comes the last question. Another tricky question from Dr. Othman. This is the terminal- This was not tricky. I was surprised. Actually. This patient, this is the terminal ileum, if you see cal valve, and we have the blue and white are, so which is which? Which is adenoma? Which is the normal? Or both are normal? We don't know. So they said that the blue, most the blue indicates the normal and the yellow indicates the adenoma. Actually, it is the other way around. Really? In this case. Yes, because you can see here, actually all the adenoma was all of this. That's the yellow part with the only normal, the lice in this lesion. What do you think, Professor Yohairo? I really wants to have chromoendoscopy spraying in the coming, then we can get much more information. Usually, at the ileocecal valve, majority of the surface structure look like a virus surface. Therefore, at least at the 11 o'clock on the lower image, it looks like a virus pattern. That's why I imagine that surrounding mucosa was the healthy mucosa and only yellowish area, which looks a little bit brownish, was the neoplastic. But I was wrong. Actually, this lesion is, it's the other way around. So the adenoma, so I spent 20 minutes looking because this was referred to me biopsy proven adenoma. And then I was in between which one and which one. If I show you the video, you guys will notice that that's in the upper image here, you will see the border and you're gonna see the normal lice. So where the normal lice start is the normal part, which is the lower part. And all what above it lost the vellus pattern is tubular adenoma. So I did 75% circumferential resection of the IC valve and it came back as an adenoma. So- Oh, that's crazy. This is a very tricky but, but now I would like you to look at it again and look at the vellus, especially at the lower image, you'll find that the yellow part have the lice everywhere. And then once the vellus end, you will find the area that has no velli, which is the adenoma. And I found that there is a border on the upper image, nearly 12 o'clock side, there is a certain border between the normal ileum mucosa and the neoplastic tissue on the upper side. Yes. So if we spread indigo coming, we can easily recognize the velli as a background of the ileum mucosa and we can easily see the border here. Yes, agree. Yes. I congratulate you, Professor Altman, for this. This is a really weird, interesting case because if I just do like a terminal intubation, I found this, I could pass this as normal by the way, but the border is really clear with a narrow band image the border comes clear. But the thing is, it's really very tricky. So I think there are a lot that we still need to know about more, about lesions, especially in some areas that are not that common where literature is a little bit deficit like the ileocecal valve. It's a really amazing case. The ileocecal valve, the trick here that you have to see normal vellis. If you don't see the velli, then this is not a, there's something going on while you're not seeing the lines. Yes. So I want to thank you, all of you about the panelists, the ASGE Eric, the ASGE guys, Eric and Michael for the nice organization. And at the end, I need an advice from all of the panelists, starting with Professor Yahagi, Professor Altman, and Professor Kainam, how to improve our lesion characterization skills. How do we train ourselves to improve our lesion characterization skills? So can we start with Professor Yahagi, please? I think at the beginning of the inspection, we should clean the lumen completely. That is the first step. Then we should carefully observe the surface structure and discoloration. And if there is any suspicious area, please use image enhanced endoscopy which is really helpful. And please use a high enhancement, surface structure enhancement, such as A7 of Olympus endoscopy. Then you can easily understand the character of the target lesion. Those kind of tiny step makes huge difference. Thank you. Oh, Professor Altman. I feel like using a cap. Yeah, I know it's very basic, but using a cap is important because in the United States, a lot of us do not use a cap. During EMR, so number one is a cap. Number two, anytime you see a lesion before you dissect it, even a tiny, small polyp, do MBI, then you will learn the difference. And it was time, look by MBI, look at your result till you learn. And then I can't wait to look at even better imaging, like with the newer scopes now, especially with TXI and other, I think we might have evolution in how we are evaluating this lesion. We had few lesions here that had different opinion about it. This duodenal lesion that Professor Rehage showed, I would remove it by ESD. I wouldn't think that there is a cancer there. It was a T2 tumor. We saw the terminal ileum lesion. So I agree. There is still more to learn, but it's a long journey and you do it one step at a time. Yeah. So, Dr. Condon. Yeah, I mean, again, thanks for the great lectures and comments, guys. I want to actually take a little bit of a step back and say, I think we need to catch our trainees, right? And then talk to them. So whenever I staff a procedure with a fellow, first thing I said, so narrow band down, don't talk to me until you do that. And then I try to walk them through. I don't take too long. I don't want to make it burdensome and I want to make it something that they start to resent. I'm like, oh, Dr. K always says NBI. So I teach them and it works. You know, when you start with simple hyperplastic versus adenoma and then tubular, they just get the sense of confidence just as the mature their colonoscopy experience. They mature with this imaging experience and whether they do ESD or not, whether they do EMR or not, recognizing and describing a lesion really, really well, helps the referring doctor. And if they choose to go into these areas, I think they're really trained right from the beginning. So it's part of their MO, if you will. They're part of their system to look at everything like that. Now, one of the challenges I face and I have great respect for all faculty, but sometimes in this, in a crush of getting procedures done, you know, moving things forward, we don't pay attention to that. And I always often encourage my faculty, especially the junior ones who are getting their feet wet as a new faculty to, hey, think about these things. It's useful for you to make it part of your practice, but also to then transfer this to a new generation of trainees. So I think lesion recognition while it is extremely important for people like us who do these complex procedures, I think it is equally, if not more important for our trainees and the general gastroenterologists who need to recognize this so that they can refer it appropriately. So I think it's equally important to focus on both areas. And I think this first effort organized by Shyma and so nicely presented by Dr. Othman and Dr. Yahagi is a good first step towards that. Yeah, that was my comment. Thank you again. Okay, thank you all. So to sum up, lesion characterization is a crucial step. We have to learn more and more about it if you want to do advanced endoscopy. So this is a baseline that we should all like spend a huge effort on it. Clean your field, put a cap, spend some time. And for me, an add-on tip, just challenge yourself with a pathologist. Expect the pathology. And when comes the final results, this makes you learn. What is this lesion that makes you learn? So at the end, I want to thank you all. And I really want to take this as a nucleus to start because this kind of, this lesion characterization needs huge efforts from experts. And this lesion characterization, it could be learned online. This is not like doing proctoring for some advanced complex procedures. This is things that is really crucial. It's important for everyone. I can see the name of the attendees. We have experts attending this webinar and I'm so, so honored and happy to have them with us. So I think there are huge efforts and still there are a lot that we need to do about this. Thank you all. And I wish we can do this again. Please do this again, Professor Yaghi and Professor Oatman. I know that you're busy, but please do. We have to go on with this. Okay, thank you all. Thank you so much. Yeah, thank you. Thank you, panelists. Thank you for everything here. This was amazing. And thank you everyone for joining us tonight. So that concludes today's event. Have a good evening. Thanks all the attendees for being with us to the last moment.

Gastrointestinal Endoscopy

Lesion Characterization

Narrowband Imaging

Chromoendoscopy

Magnifying Endoscopy

Signet-ring Carcinoma

NICE Classification

JNET Classification

Endoscopic Mucosal Resection

Endoscopic Submucosal Dissection

Granular Lateral Spreading Tumors

Non-granular Lateral Spreading Tumors

Enhanced Imaging Techniques

Gastroenterologist Collaboration