All right. It's 12.15, so we're going to get started. Just to be respectful of everybody's time. Well, thank you so much for being here. And I think one of our favorite topics for all GI doctors during lunch is to talk about colompolyps. So hopefully, we're all pretty immune to this. But it's truly a privilege and honor to be here. I'm so grateful to the course directors, the AGA and ASG, for this opportunity to speak and true privilege to talk about this topic very near and dear to my heart and almost anyone who deals and does colonoscopy, which I'm sure is everybody in this room. So I'm Mohammed Bilal. I'm the director of Third Space Endoscopy and associate professor of medicine at the University of Colorado. And here to talk about EMR and ESD for colompolyps and how do we position this in our current therapy. So let's see if I can use this slide. These are my disclosures. So objective of today's talk. So the first important thing we're going to talk about is lesion assessment. When you see a polyp, what are the features we need to look at? Then to answer the question whether I can resect this. Can anyone endoscopically resect this? What are various approaches and techniques and tools that are available to resect large polyps in 2025? And what is the right approach for each individual lesion? And then discuss a little bit about post-resection management. Before we go deep into the talk, the disclaimer I want to give about this is there's extensive literature on colompolyps. This is what we all do all day long, remove polyps. Some of us remove larger polyps like myself, but we are all removing polyps. And the main focus of today's talk is to understand all these newer tools and techniques that we have for removing these polyps is that how do we approach those and acknowledge that no one size fit all. And if you had 20 endoscopy experts in this room, we will all disagree multiple times on what approach for each polyp. But there's still some consensus upon things. And my hope is to convince you and use data to guide this. But eventually, what I always teach our fellows is that what is the eventual goal of resection? And that's what's important when you're choosing a strategy to remove a polyp is that you have to remove a polyp safely and you're able to minimize recurrence. As long as you can accomplish those goals, regardless of what technique you use, it does not matter. But our hope is that some of these techniques are much safer, some are better in certain select polyps, and that's really what we're gonna talk about today. So before you see a polyp, you're doing a colonoscopy and there you are, you find a large polyp. What's the most important thing is not to just go and attempt resection. Because obviously when we see polyps as gastroenterology, the first strategy is to go at it and try to remove it. But just like in physical exam, inspection when we need medical students is the most critical part of a physical exam, similarly in polyps, looking at the polyp and truly understanding what this polyp involves is important, and more than just the extent or the size of the polyp or location of polyp. The key question that we all have to answer is, is there a presence of submucosal invasion or cancer? Because if those features are not present, almost any polyp is removable through endoscopy and we're gonna go over that today. So there are several classification systems that are available for resecting polyps. The most commonly used, and they depend on polyp morphology, the polyp histology, or the polyp appearance. This is the most commonly used classification, the Paris classification, to evaluate polyp morphology. So this goes over whether the polyp is polyploid, is sessile, is elevated. And then there is the NICE classification, which uses narrowband imaging and is able to predict the polyp histologies. This is probably the most simpler polyp classification that when you start tackling large polyps, if you're not doing that already, is what I recommend our fellows to start with because it differentiates the histology of the polyp in three simple types using narrowband imaging, which is available nowadays in almost all modern colonoscopes. And if it's a lightish color polyp on NBI, the pit pattern is not as prominent. It's typically a sessile serrated lesion or a hyperplastic polyp, depending upon the location. If it's a more brown or a grain-like, gyri-like pattern, then it's typically a tubular adenoma. And then type three, when you start seeing the loss of pit pattern, that's when it is a deep submucosal invasive cancer. And this is a more advanced classification, which we use, for those of us who do ESD, we do use this, which is the KUDO classification. This is a schematic from one of my residents who published in his paper in endoscopy, who's right here, Dr. Wilson, who draw this, which goes over on polyp features and how the KUDO classification uses that. And basically, again, if you see irregular arrangements of pits, you see loss of vascular pit pattern on chromoendoscopy or narrowband imaging, that's a KUDO5 lesion, and that's invasive. That means it's an invasive cancer. So those are all features, but I'm sure just like, for those of you who don't do this every day, going through all these classification systems, it's really challenging and it's kind of an overwhelming amount of information. And then there's laterally spreading tumor classification, which divides the polyp into granular and non-granular. To keep it simple, if it's granular, it means it's good. So G for granular, G for good, it means a good histology, favorable histology for endoscopic resection. And non-granular means NG, it could be non-good, meaning there's higher chance of having covert submucosal invasion. But I think what's really important is that all these classification systems are great, but even among experts, especially in the West, you know, in the East, where ESD was pioneered in Japan and Asia, people are very good at predicting polyp histology. But in the West, we're not as good at looking at these things. And the studies have shown that among experts, there's not a clear consensus or an agreement on which polyp features predict what histology and morphology. So the way I think about it, what are you using all these classification systems for? And you're really just using them to predict if there are deep submucosal invasion or is there submucosal invasive cancer? So what features predict that? If you see ulceration on the polyp, if there's irregularity, non-granular polyps are more likely to harbor covert risk of invasive cancer. If there's firmness or cold convergence, areas in polyp which do not lift are sometimes considered invasive, although if polyps have been previously intervened upon, you could have what we call as a pseudo non-lifting sign, that they give you a false feeling. So non-lifting alone or central depression alone is not always a feature of malignancy, but it's certainly a higher risk. And then obviously NICE type 3 or KUDO5 lesions are ones that do not, that have higher risk of invasive cancer. So once you've kind of spent your time and try to answer these key questions, is what is the polyp morphology? B, what is the predicted polyp histology? And C, is there any risk of submucosal invasive cancer or not? Then you're ready to go over the next step, which is can you remove this polyp? The most important thing about a large polyp resection is you do not want to start a polyp removal and then realize midway that you can't remove it. It's only start resection if you can complete it, because partial resection or attempts at resection cause submucosal fibrosis, which makes future resection challenging and may unnecessarily lead patients to surgery or morbid procedures that are avoidable. The next question you ask yourself is, can you resect it? But can you resect it today? You know, if you're doing 16 colonoscopies that day and you see a large polyp, then the next question you have to ask yourself is, do you have time to do it today? You may be the right person to do it, but you may not be the right person today to do it. Can anyone else resect it? Is there a colleague next door or your group or your local tertiary hospital who has expertise in resecting advanced lesions or polyps? Think about consent, you know. Is this polyp higher risk for perforation? Is your location unstable? Are you in a difficult situation with blood thinners? Do you have an appropriate consent to tackle this? And then if you can't, you know, the recommendation would be to place a tattoo, but it's really important to not tattoo within the polyp because it can cause submucosal fibrosis and scarring. You don't want to tattoo in rectum or cecum because we all should be able to know what a rectum and cecum is and don't need help identifying that. Always tattoo a few centimeters away from the polyp because the tattoo always dissipates. So even if you put a little bit tattoo, you go back in, and eventually the tattoo dissipates and you realize that it goes underneath the polyp, leading to submucosal fibrosis and making it challenging. And appropriate photo documentation for the tattoo, like where did you tattoo, what wall it is, so it helps for future resection. And do not lift with tattoo. You know, when I was a fellow, you know, a lot of times we'd get referrals where someone tried to lift a polyp with tattoo and they thought, if it didn't lift, at least we tattooed it because that's going to make it really, really challenging for us to remove these polyps in the future. Now you're ready to resect. So we, over the last decade, we have had enormous improvements in techniques development for resection. There's the conventional hot EMR, cold snare EMR, underwater EMR, ESD, full thickness resection. So how do you choose what is your toolbox and does it really matter? Could you just, you know, pick one strategy and go with all polyps? And hopefully, my hope is that by the end of this talk, we'll have a systematic approach. And what I am a big believer in is the right, all these techniques are helpful and we need to figure out what technique works best for what kind of polyp. And we've gone from a universal strategy for polyp resection to now where we advocate for a lesion-specific resection strategy. So for resection, the most common thing that I get asked is what's your favorite snare and what kind of snare do you like? And again, no one size fits all, but for typical large polyp resection, especially if you're going to do a conventional or hot EMR, as we call it, which means you use electrocautery, you know, a stiffer snare, 20 or 15 millimeters safer because it is less likely to go through the muscular spropriand, less likely to cause perforation. But sometimes you need a smaller, thin wire snare. So the wire, the snare wire is basically this wire. What is the diameter of the cutting wire? Because the thinner it is, the more likely it is to cut. So we're going to talk more about when you do cold resections, you want a snare with a thinner cutting wire because just like a thinner knife cuts better, a thinner snare will cut better through these polyps. The next question is, you grab the polyp, what do you use for electrocautery? You know, when I was a fellow, we were always confused. Everybody's looking around in the room and like, who do we need? You know, yellow or blue pedal, and nobody really knew. So what is the right answer? Is that it does not matter. We have now data in the fashion of randomized control trial that shows that the yellow pedal, the cutting current, versus the blue pedal, the coagulation current, is similar in terms of recurrence as well as adverse events. So what I always tell our fellows, use whatever pedal your tenant tells, because it does not impact your outcomes. But it's important to understand the principles of electrocautery that typically we think that if you use the yellow pedal, the cutting current is more likely to have more delayed bleeding, versus the coagulation pedal may have more, sorry, will lead to more immediate reassurance that there's less bleeding right now, but you may have more risk for having delayed bleeding because you're just immediately causing coagulation. So the next thing is, you know, you do a polyp here. So this is a polyp that we're removing here. You'll see we're using a submucosal injection to lift. There's lots of commercially available lifting agents, or just saline, methylene blue. And then after you've created a lift, which means that you've separated the polyp from the muscular aspropria, so you've created a submucosal cushion, you get your snare around it, you try to grasp the lesion, and then what you see here, what we're doing, is what we call as a shaking and baking, we're tenting the polyp, and the reason is that the thermal energy is not dissipated at one spot. If it's dissipated at one spot, it's more likely that you could have a perforation. And then the other thing that you'll notice in every resection, or every part that we're resecting, is that we're basically anchoring our snare at an already previously resected area, so you're not leaving islands of adenoma behind. You know, the more you go into large polyps, we have to start thinking of ourselves as oncologists, or surgical oncologists, and it's really about microscopic, making sure there's no microscopic neoplasia or dysplasia left in these things. Next thing, when you remove the polyp in this polyp, we remove this in piecemeal fashion, meaning it was removed in two or three pieces. It's really important that, you know, even though we've removed all visible adenoma, that there's no microscopic evidence of recurrence left. And how do you minimize that? It's by ablating the edges. Most recurrence, as we stand today, we believe it comes from the edges of the polyp. Now, there are studies going on that eventually may change our paradigm that polyp recurrence can occur from the edges and the base, but as we stand today, you have to ablate the edges, because, and what you're ablating is not residual polyp. It's really important to know, you do not leave visible adenoma behind. You always have to resect it, because if you ablate it, it will likely recur. What you're ablating is a healthy margin on the sides, so that if there's any microscopic evidence of adenoma that you're not visibly able to see, you're reducing that. And again, data in the fashion of randomized control trials shows that there's significant reduction in recurrence if you ablate the edges. And the next question is, how do you ablate the edges? And we have argon plasma coagulation, or you can use the snare tip and use the soft coagulation setting to ablate. And again, this randomized control trial shows that is, that snare tip soft coagulation is slightly better than argon plasma coagulation. Obviously, it's cost-effective, because you already have the snare out, so you don't have to re-bring the ABC catheter, or open a new catheter to reduce recurrence. So my preferred strategy is to use snare tip soft coagulation to ablate the edges of the polyp. So here, you'll see the video. All you do is just take the tip of the snare out, you make sure your settings are chained now to a soft coagulation mode, and then this is the polyp that removed in the transfer skull, and you can see, I'm just painting around the edges, circumferentially around the polyp. It just adds another couple of minutes to the procedure, and this is all a bit, you know, normal base, or the edges of the polyp. It's not, we're not removing or ablating any visible adenoma. So this is your conventional EMR, that we were all taught, and we've learned about. But over the last decade, there's been this cold revolution. So what does this cold revolution even mean? And we hear about it all the time, is that basically, you're removing, or resecting a polyp, without using electrocautery. So you're just using a cold snare to remove the polyp, and you're transecting the polyp by just the mechanical force of the polyp, versus using electrocautery. So you can use any lifting agent you want, whatever your choice. I typically add dilute epinephrine, but extremely dilute concentration of epinephrine, like one in 100,000, or one in 200,000, because epinephrine can cause some transient pain after the procedure. And the epinephrine is not to reduce bleeding. It's just to reduce the oozing, so I have a better field of view. Because when you have oozing in your field of view, you're more likely to leave residual adenoma behind. And this is where the thin cutting wire snare is really critical, because the thinner wire will cut through better. The other thing I always get from people when I give these talks about cold EMR is, they always say, well, sometimes I can't go through large pieces of tissue, then I have to switch to hot. So, and we'll show some technical videos about this, but it's really important to understand that that actually is an inbuilt safety mechanism for cold snare. Why did the cold snare, or cold EMR technique develop, is because the biggest challenges that we face with large polypore sections is delayed bleeding and perforations. So cold EMR, with cold EMR, cold snare, you're not gonna cut through muscle. I mean, nothing is zero, but the risk is extremely low, and the risk of delayed bleeding is almost negligible. And if the polyp doesn't come through, it means you have too much tissue, and you just have to reopen it and get a smaller piece of tissue. So it's actually an inbuilt safety mechanism that people will say that we have to switch to hot rather than using cold, but it basically is a piecemeal resection of polyps. This is a video we published in VideoGI from our group, where you can see how do you dilute epinephrine. You do a really dilute concentration of one in 200,000, and add it with a commercially available lifting agent. We use a three-way stopcock and really mix it really good, and in that way, it ensures that these polyps are not, that you're getting a good lift, but you're also getting some epinephrine in the solution. So this is an example of a cold EMR. So it's a pretty large polyp, as you'll see here, that will do a traditional lift with some dilute epinephrine, like I mentioned. And after you've used the lifting agent, what I'm gonna do here is I'm gonna use a really thin wire snare, as you'll see here in a second. And in cold EMR, because you're not using any heat, what you have to do is you have to take a lot of extra tissue. So at least three millimeter to five millimeter of normal tissue. So my first snare resection, as you'll see here, is almost pretty much 50% of its normal tissue. And because there is no risk or minimal risk of perforation and delayed bleeding, I can do it pretty judiciously, versus in hot EMR, where every time you're using cauterine, that tissue is at risk for perforation, delayed bleeding, thermal injury, and et cetera. So here you'll see that once we've done an adequate lift, I'll start resection. You can see 50% of my first bite is almost all cold. And then that starts with what I call the starting point. And then I use that starting point and I anchor or pivot my snare at the previously resected area and keep using that as a guide and keep resecting as I go further. And this is a thin wire snare. So again, cold EMR by definition will almost always be a piecemeal resection. But you have by now already established by your initial inspection and optical diagnosis that this bollard does not have recurrence, higher, sorry, risk factors for advanced or submucosal invasive cancer. So it becomes easier to go through with this technique. And you'll see that the most important thing that I'm trying to do is that I'm trying to not leave islands of adenoma behind. That's the most critical thing. So you'll see like I anchor the snare every time and I'm just using the previously resected area as my guide and keep resecting. And you'll see here that in a pretty efficient manner here that this pretty almost hemicircumferential polyp has been completely removed using cold EMR technique. And the benefit is because the risk of delayed bleeding and perforation is so low that I don't have to close it. So it's a very cost effective and efficient technique. So what does the data show for cold EMR? So this meta-analysis published in Endoscopy from our group a couple of years ago basically shows that the, again, the risk of perforation and delayed bleeding is really low. But what is the challenge for cold EMR? If it's so great, why don't we just do it all the time? Why do we even talk about all these techniques? Is the risk of recurrence. Because cold resection, you're typically resecting superficial layers of polyps. So what you'll see in this meta-analysis from our group is that that risk of recurrence is about, is higher than a regular hot EMR. But if you look at a sub-categorize it, the risk of recurrence for adenomas is about 70%. But the risk of recurrence for SES cells, serrated lesions, or SSLs is only 5%, which is typically what we see when we use conventional EMR. So this set the foundation for randomized controlled trials over the last two years. We've had two randomized controlled trials. This one from Europe that was published in Gastroenterology earlier this year, end of last year, which basically shows the same thing. And this multi-center first randomized trial from the United States, led by Dr. Heikepol, which was presented at DW last year, and basically shows that the recurrence rate of cold EMR for adenomas is 30% versus 14% for conventional hot EMR. But the recurrence rate for SES cell serrated lesion is similar. So based on this data, we now know that cold EMR is the preferred resection strategy for SES cell serrated lesions, given its excellent safety profile, and similar recurrence rate as compared to conventional EMR. But for adenomas, the jury is still out because you are compromising recurrence, which is sometimes challenging to manage and can be also a problem in terms of cost and repeat colonoscopies and things like that. So the third technique that sort of gained a lot of popularity over the last few years is underwater EMR that was developed by Dr. Ken Van Muller in California. And this technique is kind of, you know, if you don't do it, you kind of have to unlearn everything you've ever been taught about endoscopy and sort of relearn it in a new fashion. But the learning curve is actually not that challenging if you've already been doing large polypore sections. So this schematic from Dr. Doug Rex shows that how water infusion or saline immersion separates the muscular spropria from the submucosa. So you'll see here that, you know, by putting water, you're separating the muscular spropria from the mucosa. And for all of us who do endoscopic ultrasound, we always use water immersion to try to, you know, separate out the lesions, the layers better. So this is a polyp that was referred to me. You can see it almost involves, you know, 60 to 70% of colon circumference visibly looks like an adenoma. And here I'm just doing an underwater EMR. So the first thing is you aspirate all the gas out, and then you infuse your lumen with saline. And once you, I typically mark these polyps so I know the edges underwater because I'm not going to use any insublation. And I'm just using saline immersion to allow the polyp to float. And what saline does or water immersion does is that a polyp that was three or four centimeter has now become a 15 or two centimeter polyp because it floats into a bulkier shape. So you'll see here, we just use water, no lift, and then infuse it. It allows me to really get the polyp and the snare, tend to weigh, and then using normal principles for electrocautery, just lift the polyp away and resect. And here you'll see the same principles that I'm really, what I'm really trying to do is try to use previously resected area as an edge, and then start going further and removing these, removing these polyps. And you'll see here that this really large polyp now at the end of this video, almost hemicircumferential polyp has been easily removed. And again, no lift. You can examine it underwater and it's a really efficient technique because, and it's also cheap because you're not using typical submucosal injection to do this polyp. So what does the data show for underwater EMR? This meta-analysis from our group shows that there's decreased in recurrence as well as decreased in higher, sorry, increased unblock resection rates. There's no difference in bleeding and perforation. So underwater EMR has really become a really acceptable strategy for removing these large polyps. So we'll take a little tangent here and do a little case here. So you see this polyp in the rectum, pretty small polyp and a regular colonoscopy, you're almost done with the colonoscopy. You've already told anesthesia, it's going to be one minute and you're going to be done. What are you going to do if you see this polyp? Any takers? Take a better look. Excellent. So this is how the better look looks. It's not pretty small. What does it tell you? So if you look meticulously and carefully, this really small rectum polyp that should have been, you know, you would have been done by this polypectomy by the time we've just taken this look on this session, right? If you look at this rectal polyp, this small rectal polyp, look closely at this polyp. What you're seeing now is what we described in the first slide. There is lack of features of, you're losing the pit pattern. So what you're starting to see is that there is lack of the classic pit pattern that we discussed and this is a feature for submucosal invasive cancer. So this polyp was obviously done by, you know, one of my, one of the general GI referring doctors in the community recently and they did a cold, you know, lifted it and resected this polyp. So they even lifted this polyp, which is pretty impressive for a small polyp this size. And this is what the pathology shows. Pathology shows invasive, moderately differentiated adenopersonoma, at least invading into the submucosa. And due to tangential embedding in some sections, the margins cannot be assessed and the deep margin remains unexamined. So what does this mean is this is a non-curative resection of a cancer. So this patient now, for this small little polyp, you know, could possibly need a large rectal surgery. And this polyp is a few centimeters away from the dentate line. So the surgery cannot be a TAMAS. It's likely going to be an APR and LAR, both surgeries with high morbidity. So why am I talking about this little polyp in the middle of this talk? It's because this lost the foundation for ESD. So here's a polyp here. You'll see here in the rectum again, it's about, this is obviously a different polyp. So a lot of us will not try to remove it in our regular screening colonoscopy and think about it. But rectum is so easy, right? You have an easy scope. It's straight. Why don't you just put a snare around and start hacking at it? But what I've decided to do in this polyp that was referred to me is do an ESD. So here, so what is ESD? So ESD is endoscopic submucosal dissection, allows for unblocked resection of large polyps. So you'll see what here, we mark the polyp, we lifted it, and then we use a dissection knife or electrocautery knife here. What we're causing is creating a mucosal incision. So same principles of lifting, but you're lifting outside the polyp because we are worried that this could, you know, to make sure we get a good margin. And I'm just gently dissecting fiber by fiber after the initial lift in the submucosal space and trying to get underneath the polyp and trying to get it in one piece. This is, you'll see here that once we remove this polyp, all you see is muscularis propria. And you can see a little injury of the muscularis propria, but now this large polyp is gone. And after I've removed this, this is how we pin the specimen. So the end block resection allows us to do that. And what that does is that it makes sure that your margins of the polyp over time don't get flopped, and then pathology can better examine the polyps. So this goes back to my initial point, is that now when you remove large polyps, you're talking about oncological resection principles. And in oncology, if you've ever looked at surgical oncology, it's all about the margins and it's all about the features of the cancer. So we have to now think as oncologists while we do these complicated procedures and start doing this. So what was the pathology on this polyp? So pathology showed a well-differentiated adenocarcinoma with small focus of submucosal invasions. Depth of submucosal invasion is 277 microns. There's no lymphoblaster invasion. There's no perineural invasion, no tumor budding, and lateral and deep margins are negative for dysplasia. So I'll go over here in a couple of minutes here what this really means. So the point I'm trying to make is, does the location of the polyp matter? Does it matter where? You know, we talked about the histology, the appearance, the morphology, you know, what features we see. But does the location really matter? And then the answer to that is, yes, it does matter. So this study from Michael Burke's group actually goes over what is the risk of covert malignancy, meaning that visibly you thought that this polyp is just a normal polyp-free cancerous adenomatous polyp that you can remove, and then the pathology is a surprise there, and the pathology comes back as an invasive cancer. So the risk of covert malignancy is much higher in the left colon, especially in the rectosigmoid as compared to the right colon. So you see in the rectum, the risk for covert malignancy is 11 percent, and the sigmoid colon is 16 percent. But the reason I want to highlight the location of the rectum is because rectal surgeries are much more morbid. You know, there were risks for ostomy, which think about a 40, 50-year-old patient, 60-year-old patient getting an ostomy versus a right hemicolectomy. Yes, it's a surgery and it has risks, but at the end of the day, you know, it's not as much of a morbid surgery as compared to rectal surgeries. So yes, the answer is that rectal location or location of the polyp does matter. And the first thing when you embark on ESD is to understand these definitions. Those were all newer things to me, you know, who learned all these things, you know, after my advanced fellowship. When I was a GI fellow, we weren't talking a lot about these things, which is ironic because in the West, sorry, in the East, these things were already being done. So there are procedural definitions of an unblocked resection, which I've been talking about, which means that we got the polyp out in one piece. And then there is piecemeal resection, that you got the polyp in multiple pieces. And then there is, more importantly, the histological resection, which is an R0 resection. So R0 resection means that your lateral and deep margins are negative for the highest degree of dysplasia or any dysplasia and carcinoma, and an R1 resection is one of those margins is positive. So R0 resection is what we call as a curative resection. And that's why ESD formed in Japan in the 1990s, and now finally over the last five to 10 years, we're starting to see update in the West. So what is the benefits of ESD? It's got a higher R0 resection rate, higher unblocked resection rate, and it's curative resection for early cancers. You can cure an early superficial cancer and prevent the patient to need major operation in the GI tract, whether it's the esophagus, stomach, colorectum, and it allows for better pathological assessment. Because probably a lot of these polyps, we're getting them with a snare, but the pathologist cannot confidently tell us, and if they can't confidently tell us, we can't confidently tell the patient that you've cured a cancer. So that's why it's really important. You'll see here some examples of large unblocked resections that I have done. So what are the indications for ESD? Oh, it's so great. You know, we can fix everything with ESD. Every polyp should get an ESD. Why should we even talk about EMR? You know, because ESD is technically challenging. It's difficult. It's not everybody can do it. There's a cost to it. There's a time commitment to it. So what are the indications of ESD and how do we approach that? So obviously, if you know that there is a submucosally invasive cancer, and you can predict it, and you know from pathology, then you need unblocked resection. So all type 5 lesions, if they have a depressed component, complex morphology, location in the rectal sigmoid especially. In Japan, ESD is the predominant strategy for all large polyps. But in the US, based on what I showed you, what we understand is that probably the rectal sigmoid is what makes the most sense for the vast majority of people. There are obviously some experts who can do ESD in the United States for every lesion. Non-granular, remember going back to optical diagnosis, non-granular, NG is not good. If there are granular adenomas, but they are laterally spreading greater than 2 to 3 centimeter or a recurrent or residual polyps because traditional EMR is challenging because we cannot create a submucosal cushion because of submucosal fibrosis. And then what is a curative resection? So a resection, to confidently be able to tell a patient curative resection because why it's important is that even though you may have gotten all the margins of the polyp out, there is still a risk for lymph node metastasis. We as endoscopists cannot do lymph node dissection like the surgeons do, but not every patient needs that. So which patient you can consider a curative resection? So it's a T1B cancer with depth of submucosal invasion less than 1,000 microns. So what that means is that the pathologist actually look at the submucosa and think of that as three, in three halves. And if it's invading the superficial submucosa, that's typically 1,000 microns. So that's considered to be a curative resection. Polyp differentiation. So not every cancer is the same. The cancer biology is critical. So if it's well to moderately differentiated, that's a good prognostic feature. If they don't see lymphovascular invasion, no perineural invasion, and there's low tumor budding, those are all good prognostic factors. And if I have all these in my pathology report, then that's a curative resection. You can tell the patient with confidence that the risk of lymph node metastasis is really low and this resection is considered curative. Obviously, you know, you always want to review these cases in your multidisciplinary cancer conferences, tumor boards, and it's a partnership because it truly is multidisciplinary management. And finally, the NCCN guidelines now have incorporated, the National Cancer Guidelines have incorporated ESD with these features as part of cancer resection algorithms in the GI tract. And this is a really nice schematic from Dr. Dragunov and Dr. Yang published in CGH on how we approach, how they approach, or they recommend approaching ESD in the United States or in the West. So if you see overt signs of cancer, if it's clear it's a cancer, there's no point in even trying to remove endoscopically because you can cause more harm. So then you biopsy, you tattoo, and you refer to surgery. If you're not sure, then send to someone who does these procedures. If you are not, if you think that there is no signs of deep cancer, but there may be superficial submucosal invasive cancer, all the features we discussed, then yes, ESD is the preferred treatment for those lesions because you could potentially cure them through endoscopy. So going back to my point, so then why just, why not just ESD? So finally from Europe, people are like, oh yeah, why is, why don't we just do ESD? It's so great, you know. So this is the first randomized control trial on EMR versus ESD in the West and from Europe that were published in the Annals of Internal Medicine in 2023 that looked at 360 patients and randomized to either EMR or ESD for polyps greater than two to three centimeter in size, and they noticed that recurrence for ESD was only 0.6% as compared to EMR of just 5.1%, and there was zero cases of recurrence in R0 resection. However, the adverse events are 35% for ESD, and these are world experts in ESD. So how do we put this all together? You know, this is again a lot of, lot of data, a lot of different things I'm telling you. So this, another paper that came from Michael Birch's group in Australia looking at 2,900 large polyps greater than two centimeter, and they looked at right colon polyps, right, the area where ESD is challenging because, you know, the colon, your scope's unstable, it's a difficult position, difficult location, and they saw that only 0.7% from 3,000 polyps, almost 3,000 polyps had features of superficial submucosal invasive cancer or low-risk cancer where endoscopy could be considered to be curative. So based on this algorithm, they found that you'd need to do 140 ESDs in the right colon to be able to cure one cancer. So why does this matter? It means that location does matter. So putting this all together, what do we do? I've told you all these endoscopy resection techniques. What technique do we use? So this is an algorithm that Heiko Pohl and I published in CGH last year, which basically simplifies this question, especially in the United States or the West. If you see a large polyp, first question, are there features to suggest submucosal invasive cancer? All the things we talked about are listed. If the features are present, if it's in the colon, especially right colon, then probably surgery or trying to get on block resection. Or if you have true great expertise in ESD, which a handful of people in the United States have, then ESD is the preferred. But in the rectum, because of features we discussed, rectal surgeries being morbid, rectal ESD being safer, and the higher probability of covert malignancy in the rectum, ESD is the preferred strategy for rectal sigmoid polyps. But if there's no features of submucosal invasion, then you go back to your optical diagnosis and think about the predicted polyp histology. Is the predicted polyp histology, do you think it's going to be an SSL? If you think it's an SSL, cold EMR is the preferred strategy based on data. If it's an adenoma less than two centimeter, then you can do either cold or hot EMR. But for adenomas greater than two centimeter, you need to do either hot or conventional EMR, given that we know the recurrence rates are higher with cold EMR in this polyp strategy. So, once you've removed polyp, you know, then what? You're done. You come out. Well, then we got to think about closure, because especially if you use electrocautery-based techniques, you know, you're at higher risk of delayed bleeding and perforation. And this is, again, a randomized control trial showing that defect closure from Dr. Pol's group, that defect closure for these polyps actually reduces the risk of delayed bleeding and adverse events. So we know that we have to do defect closure. However, even in this randomized control trial, you know, which consisted of world experts, there was almost 33% of polyps were not able to have complete closure because closure is hard. But since then, we've had a lot of new advances in closure techniques. This is a through-the-scope suturing device, X-Stack, and preliminary data from the West Virginia group here showing the efficacy of X-Stack closure for closing defects. But there's been novel advancements in simple closure techniques like tissue approximation techniques. So this is a novel clip, which is called the dab clip, where it has two prongs that are independently operated. So here you'll see that it's a polyp that I would probably end up needing 7, 8, maybe 9, 10 clips to close and pre these clip techniques. Now I can grasp one side, open the other prong of the clip, move it to the other side, and easily approximate it in a few minutes. And this makes closure really easy, as you'll see here. And once you've approximated it, you could, because you're independently operating those clips, and your nurse or tech is opening or closing one arm, and then you close it. And then I'll just, you know, complete this closure with a couple other regular through-the-scope clips. So a closure that would have taken me about 20, 30 minutes, I can easily do in 5 to 10 minutes now. Similarly, a more easier-to-use device, because it operates like a normal clip, is what we call a mantis clip, which also came out a couple years ago, in which you use the same clips. It rotates just like any normal clip. Your nurse and tech doesn't have to do any learning curve for it. You grasp one side, but it has these prongs on the clip that make sure that the clip stays, that the mucosa stays held, and you can move it to the other side. And as you'll see here, when I open the other side, the clip's still holding the previously captured mucosa because of those prongs. And again, really easily, you can approximate this and close this defect. And then I'll just supplement this with another additional 2 to 3 clips to be able to close this defect. So this is a data multi-center study that we are also part of from Dr. Yang's group, which basically shows that now, with these approximation techniques, we're able to accomplish 96% closure for large polyps greater than 2 centimeter because of these advancements in these techniques. But the challenge is, if you're going to be doing large polyps, it's all great. It's all fun. You can remove all these polyps. It makes you feel really good. We're really preventing curing cancer. But, well, yes, well, two things still continue to remain a challenge. One is recurrence, that if you do enough large polypectomies, you will have recurrent polyps. And then second, we're going to talk briefly is adverse events. So the good news is that we, in 2025, have a lot of tools in our bag that most recurrent polyps, despite how challenging they are, are able to be managed endoscopically. So you can do repeat EMR. You can do hot forceps avulsion. You can do cold avulsion. You can endoscopic full thickness resection, endoscopic power resection device, ESD. And rarely, we still need surgery for these recurrent benign polyps. And eventually, this involves talking to the patient and figuring out the patient goals and having a shared decision making on what's the right technique to use. This tool was developed in Australia. It's called the Sydney EMR recurrence tool that look at different features to predict recurrence. And the things that are highest risk for recurrence are size greater than 4 centimeter, intra-procedural bleeding, because it obscures visualization and your ability to ensure that you've got an all adenomatous tissue out, and then presence of hyperdysplasia. And the authors conclude that if the score is zero, then you can even forego the surveillance colonoscopy. So hot avulsion is a very easy and simple tool, but very effective. You basically use the hot biopsy forceps. This is the only time now in our lab that we ever use the hot biopsy forceps is to do avulsion, because it allows for both resection and thermal effect to destroy the polyp. Remember, ablation alone is not enough, right, because it will recur. And you just grasp it, you tend it back, and then you're resecting using electrocautery at the same time. This is another strategy to remove polyps is what we call the endoscopic full thickness resection, which is a device of non-exposed full thickness. So even though you're resecting all the way to the serosa, you're never exposing the peritoneum. So here you'll see is a polyp that's been intervened upon three or four times, but still recurs, was referred to me, where, you know, we're marking this lesion, and then we're going to use this device that already has a clip and snare inbuilt in it. So you go in, you grasp the polyp with the forceps, you make sure you bring it into a cap, which has an ability to deploy the clip at the same time. So whenever you have the polyp enough in the clip, you're going to see here, we're going to deploy the clip, and then the snare is already preloaded, and then you're going to use to close the snare and resect the polyp at the same time. Once you see here, we finished the resection, you're coming out with everything, and now you go back in to take a look, and you'll see here serosal patch consistent with full thickness resection. But even though you see serosa, you already have closed it before, so you never expose the peritoneum, and because you've cut all the way, the recurrence rates are very low. Now we have data in the form of meta-analysis that shows that for a majority of the recurrent residual complex polyps, you have at least R0 resection rate of 78%, which is pretty good for the kind of polyps that we do. This is another device that we use sometimes for removing these polyps. This is the endoscopic power resection device. This was the first video series that our group published using this device. Sometimes with this large at full thickness resection device, it's challenging to go through the sigmoid colon or tight areas, so we cannot get there. So we use this where you lift the polyp, and it's basically a morselator device that was initially developed for necrosis that we've now started using for polyp resection. And it basically debrides the polyp tissue and resects it in a fashion. So this is also another tool in our bag, and here you'll see that you just keep morselating the recurrent polyp. It's a little challenging to control this sometimes, so it's a little bit more time-consuming, but you'll see it does finish here. You'll see at the end of this procedure that we've completely removed this really challenging recurrent and scarred polyp that was so scarred there was no way to lift this polyp through mucosal resection techniques. This is a technique that we've pioneered, which is the hybrid ESD-EFTR technique, and this is taking it one step further for really challenging early GI tract cancers. You can use a combination of ESD, because the challenge with these lesions, they're so fibrotic that they're not easily pliable to be grasped into the full thickness resection device. So here you'll see that I finished the dissection procedure initially to create a mucosal incision and dissected a little bit to make the lesion more pliable. So once the lesion becomes more pliable, I can incur the grasp for both sides of the lesion, and we're able to resect this tissue in and then able to subsequently resect this polyp. So you'll see once we get it in, but now this lesion, which is very fibrotic and invasive, easily comes into the calf because we've made an incision around it and disconnected the area. Because the tumor is typically more invasive in the base and the edges are not, but you can see a really nice R0 resection we got for a T1SM1 cancer with negative margins on histology. And this was our first case of this technique that we actually used to resect a T2 cancer, which is obviously not standard of care. But for a non-surgical candidate, we were able to use this technique and publish in GIE a couple years ago to be able to remove this. So just kind of give an idea of how the field is progressing and how much deeper we can go. But the challenge that remains in these cases is that I cannot confidently tell this patient that you're not going to have lymph node metastasis. But the patient is never going to get surgery because they're not a surgical candidate, so they were put on adjuvant chemoradiation. So what are some of the colonic EMR practical considerations and tips that I always keep in mind? Think about consent. Always, always use a distal attachment cap because it will make it easier to anchor yourself around snares. Take your time. Don't rush. Don't see a polyp and just jump at trying to remove it. Take your time. Don't start what you can't finish. I typically, for right colon or typically challenging locations, I use a pediatric colonoscope because it's easier to maneuver in retroflexion. And what is my personal preferences for these polyp techniques? Like I said, if it's an SSL, I do cold EMR. If it's an adenoma less than 2 centimeter, I do cold EMR. If it's an adenoma greater than 2 centimeter, I either do a conventional or underwater EMR. If it's a rectal lesion greater than 2 centimeter, I prefer on-block resection and typically with ESD because with the things we talked about, the risk for covert malignancy is higher. Even with the higher recurrence rate with the large polyps, if it's an unstable location, patient lives really far, they're in blood thinners, they have multiple core morbidities where I feel like if I have a complication, the patient won't tolerate, I still sometimes do a cold EMR for these things. If they've had previous attempts or severe fibrosis, I do underwater EMR or an FDR procedure. Eventually, the most important thing is what the technique that's best is what gets the polyp out, minimize recurrence, and you can do it safely. But despite all these cool stuff, one of the things that I lose sleep over is that we do have adverse events. When you go to large colonoscopy, it's a very safe procedure, but as you embark on larger and complex polyps or higher interventions, the risk of adverse event increases. And we need to be comfortable. If you're going to embark on large polyp resection, you need to be prepared that these adverse events may happen. We use all the things we talked about today to minimize these, but when they happen, you need to be prepared to do it. So you're doing a colonoscopy, you're now become a master resectionist, and you have a complication. Typically, the most feared complication of all GI doctors still remains is perforation. So for complication, it's important to recognize that early recognition and management is key. Even when I was a GI fellow, that was not very long ago, we had a culture. If you see peritoneum, you came out as fast as you can, and you called surgery as fast as you can. But now there's a culture change, and my advanced fellows here in the audience, they'll tell you, if you have perforation, first thing, you say some words that I can't repeat here. And then I take a deep breath, and then you have to remember that most complications in 2025 can be managed endoscopically by you or someone else who's expert in these techniques. So this is an article we published in Gastro a couple years ago where we introduced this concept of scopemanship or scopepersonship. With Dr. Belipo from Australia leading this work, which talks about similar to sportsmanship, sportspersonship, where you see where it's not just about how good you are, how skilled you are, but it's about a team and remaining calm. So communicating with your team, showing the highest degree of leadership, because you're the leader. We expect to close this, but you need your nurses, you need your trainees, you need your staff. If you're in a private practice, you need your anesthesiologists, you need your surgeons, you need everybody on board. So really empowering your team to work in their best environment, and that means that as an endoscopist, you have to stay calm and remembering that there's a lot of things in your toolbox. But the challenge with perforation management is really that what happens if the patient becomes unstable? Because once you have pneumoperitoneum, you're not going to have all the time to stay calm and just think about leadership and think about all these things. Because the patient is, the anesthesiologist is like, patient's hypotensive, their ventilatory pressures are high, what do you need to do? And they're right, because this could be life-threatening. So this is where a very simple, cheap, cost-effective, easy-to-do maneuver of needle decompression is important. So here you'll see I'm doing an ESD for a colon cancer in the right colon, and I've seen what no endoscopist would want to see is yellow, glistening fat right in my face. Patient's unstable, so what we do is we do a needle decompression. We use a 14-gauge or 16-gauge needle. Here you can see the glasses of Dr. Carrillo here is in the audience to help me do this procedure. And what you'll see is that we are, we just basically put a needle, we all do this for PECTU placements. And then you leave the sheet in, and here you'll see me stressed out, but I'm holding, and you'll see all these air bubbles in there and all the air is out. And within a span of seconds, the patient goes from blood pressure of, you know, 60 systolic to normal blood pressure, breathing comfortably. And now all you have left in there, you take the needle out, just like a PECTU, all you have left there is a sheet. Sheet is blunt, so it's not going to cause any trauma. Now what it's enabled me to do is made an emergent situation relaxed. Now I can actually do all those things, and I can take a deep breath and see whether I can fix this or do I need to call a trusted surgical colleague. In this case, you know, this is an advanced cancer non-surgical candidate, so I've decided to close it. I've finished it all to put to the lab, but I keep the patient home. Patient goes home the next day. Patient's cancer is out. It's a curative resection. I've done it all the way. I've resected the serosa and the resected specimen. And this patient who is a non-surgical candidate gets a curative resection, and this could easily have become a more challenging situation. So then the next thing, when I started giving these talks, people were like, well, how do you do it? Everybody keeps asking, so we put out this video in VideoGIE that goes over step-by-step algorithms. So, you know, you can look at it on YouTube. Within the moment of a perforation, figure out how to do this needle decompression. There's zero learning curve needed to do it. We all know how to put a needle in something. We do a paracentesis and remove the air out. So with this, thank you so much. I do want to leave some time for questions and answers, and happy to take any questions, answers. Thank you for your attention. Excellent talk, Dr. Pillal. If you have a large lesion in the rectum, would you like to do an EUS to see if there are lymph nodes that are involved or go with the EST? Yeah, so that's a great question. I mean, we know that EUS is not very good for accurate staging of early GI cancers. So obviously, if it's a for-sure cancer, then they need to go to surgery. But if you can see optically, typically nowadays we use optical diagnosis to determine if it doesn't look like it has features of deep invasion, you do EST. Because EST will be curative. If not, it will be the most accurate way to stage it. Because we know from studies that there's a lot of variability between T1 and T2 cancer among endoscopies. Thank you. Hello, thank you very much for your presentation. Very informative. I would like to ask you, how do you deal if you have a, let's say, T1 cancer in the rectum, but it's more than 1,000 micros, and no other risk factors? Now we know already that this is not such an important risk factor for lymph node metastasis, the submucosal invasion. Would you refer to surgery, or you just watch and wait? So I think what you're asking is what happens if you have no other risk features, but the depth of invasion is greater than 1,000 microns? So that's a great question. As of guideline stand today, that is considered a higher risk feature. But there is data now that shows that depth of submucosal invasion alone is not enough to send to surgery. So in that case, it's really a shared decision making. We have, like I said, I review all these patients in our multidisciplinary cancer conference, where we review it with pathology. We make sure that all the other features, like differentiation of the cancer, you know, lymphoblastic invasion, if all those features are not present, I typically present options to the patient. And if they're young, I tell them, like, there is a small chance. I can't tell you for sure, but these are the studies that show that depth of submucosal invasion alone may not be a higher risk factor. And I really just have a discussion with them. And I've had patients who have said, there's no way you're taking out my rectum. No way you're taking out my rectum. And I've had patients who are like, I want a zero, I don't want to risk this chance in recurrence, and they end up getting surgery. So we typically do that. And I think as the data evolves, my personal thought is that hopefully we'll start seeing more and more the depth of submucosal invasion is not as important as you once thought. Thanks again for a great lecture. Question that I have for cold snare EMR, is there a role for, you know, using snare tip cautery or hybrid AP, or not hybrid, but APC after for the edges? That's a great question. So this is actually a study that we're doing right now is to look at cold snare EMR with soft coagulation of the base and the edges to see if that reduces the risk of recurrence. So a lot of us believe that it may help, but if you want a data driven answer, we don't have the data on it yet, but we should see those results in a couple of years. That's a great question. Hello, thank you so much for the great speech. And you had mentioned that well differentiated or moderated differentiated cancer is one of the key factors that you will observe it as a complete resection. But if it is a poorly differentiated cancer, but we achieve R0 resection, and also there is absence of lymphovascular invasion, per neuro invasion, or tumor body, would you recommend the patient to receive further surgery? Yeah, again, same thing as we would do with submucosal invasion, because that's what the guidelines tell us. We know that preliminary data probably shows, you know, this is, it's probably okay. But we, my practice, we review all these cases in our multidisciplinary conference, and we look at all the features. So if this is a patient who's, you know, 80 years old, not in great health, we are going to decide to do surveillance. But if this is a young patient, and you know, sometimes they'll opt for surgery. But this is always a discussion, and one of my least favorite scenarios to have, because I think that a patient's going to be okay, but I can't say with confidence. And we just need more studies, you know, to prove that whether differentiation matters as much as we initially think. Thank you. All right, any other questions? So thank you so much again for your attention.

Endoscopic Mucosal Resection

Endoscopic Submucosal Dissection

colon polyps

lesion assessment

recurrence

complications

closure techniques

multidisciplinary approaches

endoscopic techniques