this. So, end block resection when we're like reviewing literature. So, end block means resection performed in a single piece, right? R0 means that you have a resection with negative lateral and deep margins, okay? So, it's important for pathology purposes. And curative resections automatically means that you do have an R0 resection. It's well or moderately differentiated. Your subucosal invasion, at least for colon, is less than a thousand micrometers. And there's an absence of other pathologic features such as lymphovascular invasion or tumor budding. And the reason I bring this up as we do these case discussions, you know, the most challenging aspect of ESD beyond the procedure is really the interpretation of the pathology in discussing with your referring physicians and surgeons. Because a lot of the oncologists that you'll work with, you know, aren't familiar with these criteria. So, you'll get into tumor boards and things like that and you're gonna be in a very confusing situation. Now, since we're talking about basics and a lot of you are gonna be, you know, presumably starting this once you go back, you know, where is the ideal situation to do these cases? And esophageal ESD is fairly difficult. You know, it's a little bit more advanced. Gastric, as many people mentioned, we don't really have a lot of cases in North America. So, rectum is really the ideal location. So, even people like Michael Burke, who was a huge advocate of EMR, you know, they say that nearly 50% of laterally spreading lesions with subucosal invasive cancer are located in the rectum. So, this is where the major benefit of colorectal ESD can be derived, right? I doubt that many of us are gonna be, you know, going straight to the CECOM, you know, after a course like this, but rectum is really good. And, you know, the way that this certainly is justified, not only besides the subucosal invasive cancer, is that when you look at long-term outcomes and recurrence, the recurrence rates of the rectum are extremely low. In this study, one patient had a recurrence of about 1%. So, I wanted to start a discussion off, first case. So, one of the most common indications that you will get at first, because a lot of this requires like education to your colleagues, when I started doing this at Northwestern about seven years ago, you know, it was slow to get people to understand what this is and why they do it. We would get a lot of referring physicians that would send in lesions that were failed after EMR. So, that by far, at first, is gonna be your most common indication. And that's what happened in this situation. You can see that this really failed. I mean, this this lesion is like, it's there. And you can see that, you know, the scarring, you know, with the folds kind of centralizing towards the center there. And you can see on the backside, you know, what this looks like. So, you know, I'm going through here and the other thing that you'll notice is there's a lot of dark areas. So, people used to do this more, not as common anymore, but they'll actually use tattoo injection as their lifting agent. So, tattoo ink is, you know, it's an organic compound and it causes like massive, like, fibrosis. So, not only are you dealing with something that's like, you know, scarred down, but now you have like tattoo to visualize. It also causes, like, neovascularization. So, here I am, you know, with the insulated tip knife, like, doing my thing. And, you know, I get to this point and you can see here. So, the muscle fibers, and then you'll start to see these vertical fibers. This is like severe fibrosis. So, look at that. Like, that is like that thick white chunk that's all fibrotic tissue. So, you know, you're like slicing and dicing, having a good time, and then you encounter this. Right? So, a spurting, you know, arteriole, I guess you would call it. But, it's still annoying. And, right, blood baths are bad. So, this is an example of me doing a bad job of, like, trying to grasp this lesion. So, basically, when you grab something like this, you should not apply any cautery. You want to, once you hold it closed, it should stop bleeding. And, here, what's happened is I just haven't grasped it very well. So, you know, it's slowed down. So, I don't want to apply any cautery. Okay? So, you really just want to readjust, you know, some just fine movements. You finally grab the lesion. Now, you want to tent it away so that you're not applying this current to the deep muscle. So, now it's, there's, it's tented away. It's not bleeding. Now, you can apply the current and you can move on. You can see all that black, you know, tattoo and everything. Is it possible to dim the lights in the front? So, this is a tunnel that was created from the distal end. And, this is, you can see, look at all that black tattoo in there. So, that's a complete resection. Any comments from our faculty on what you guys would do in those type of situations? Or, are you seeing, are you still seeing a lot of these? So, thanks for showing that case. I actually really want to highlight that the cases that you're going to get in the U.S. are very different from these native, pristine lesions that we've been shown by a lot of our Japanese colleagues. I'd say the majority of colorectal ESD I do are on lesions like that. Failed EMR, tattooed, severe fibrosis. Very difficult to see the dissection planes because you've got tattoo ink in there. And, sort of, dwelving into ESD in the U.S. actually really means dwelving into lesions like this, Nicole. Robert, what do you think? I think, I find for lesions like that, particularly with tattoo and severe fibrosis, more recently I find the water pressure method actually quite helpful. I know Dr. Yahagi will talk about it later, but for severe fibrosis, and particularly the tattoo, I find the water pressure method really helpful in that it helps a little bit more in terms of delineating the tissue planes. So, I use it pretty routinely in those circumstances. And, unfortunately, it's not that uncommon, as Dr. Bhatt mentioned, that you do get a lot of these lesions that have been partially removed and tattoo placed directly underneath them. And that technique has really helped me a lot for those lesions. The area that, if there's a fibrosis, it's always good to start a little far away so that you can have a little bit of flap to do more traction because close to the scar, it's always dense. It's very hard to just get into the semicosal layer. So, I tend to go a little bit wider so that I can get into the semicosal layer quicker. At the same time, if you do the traction, you have to be ready that you're going to see that muscle being pulled up at the same time. So, you cannot just cut through horizontally that you're going to transect the muscle layer. You have to just try to find the layer of the, just above the muscle layer. Just caution you. Yeah, I think tattoo makes the ESD very difficult, challenging. And the case you showed, located in the rectum, right? It's not necessary to tattoo at all. Yes. That's a very fair point. That's exactly right, but it happens. We see that all the time. We see tattoos in the CCOM. I mean, like, you'll be surprised. So, one of the things I will add is, you know, how do you give this feedback, right? Like, you know, you're like cursing during this case and all these things. What I do, in a very respectful way, you know, I give these type of talks. I show these cases. I will send pictures to the referring physician saying, you know, that was a really challenging case, you know, you know, because there's some scar tissue, you know. Hey, look at this, like, you know, center and everything. You know, try to like, you know, just get the picture, like, please, like, in the future, like, if you can't remove it, please don't start it. You know, that's really the message that you want to send along. So, some of these cases are from my early experience, but I think you... Yes, go ahead. Regarding educating colleagues in terms of referral, do you tell them not to biopsy a lesion before they send it out for advanced resection, or do you kind of leave it in the air? Because I... So, the biopsies are rarely helpful. Rarely ever helpful. It's, you know, if it's an obvious invasive cancer, then obviously they should biopsy it, but if they're gonna refer for a, you know, what they think could be removed by somebody else, they should avoid biopsy. I always try to get color photos, which can be very difficult because we still fax records, and faxing, you know, endoscopy reports is not helpful. So, you know, we try. I try to get, like, their cell phone number, ask them to text me, you know, because bringing patients in and repeating procedures, you know, which can't be done is not helpful either. The only thing is... Sorry about that. The only thing is the referring MD may not be confident on the diagnosis, and we see sometimes that there's a funny thing, please take it out, and it was turned out to be just a normal mucosa. So, it's okay to biopsy in that sense that we try to educate just only a little bit biopsy, not a big biopsy, just to prove that this is need to be taken. That's right. It's hard to change people's practice. You know, we had some physicians who actually had gone out into private practice for 10 years, and then came back as faculty, and they couldn't believe when we told them, please don't biopsy these lesions, but over time, you know, you show good results, and you show them, you know, what, you know, doing like a native type of lesion without any intervention, what the difference is, and, you know, better outcomes, like you will change people's behaviors. So, this is another example. Oh, another question? Yeah, go ahead. Yeah, so, one of the alarming features that we sometimes see in potentially invasive lesions, if they do not lift adequately, but that can also be from fibrosis. So, if you see a lesion with a centrally scarred down area, which was partially resected before, is there a way to determine, should I stop instead of surgery, or maybe should I just try? So, it's exactly what Dr. Fukami had mentioned. You want to give yourself some room, so it's like, it's basically like an area to kind of like ramp into it. So, you'll find an area where the submucosa is fresh, you can dissect it, and then what happens is you can isolate that fibrotic segment, and then you can dissect that out. These can be very broad, and once you dissect through it, then you'll get to the normal submucosa again. Yes, so having that information, you know, known is certainly helpful. So, this is an example of a patient that was referred for what was said to be a large polyp of the proximal rectum. It's really rectosigmoid, and these can be particularly difficult, and again, this was like in my earlier experience, and what happened was, so I did the evaluation marking, we started the procedure around 930 in the morning, you see this, I call this blue heaven, so blue, you know, is like the safe space, right? Like, looks great. You're patting yourself on the back thinking that things are going well, and here we are like 35 minutes later, you know, I did, you know, a marginal incision, and you know, as we're starting to dissect the submucosa, you know, there's kind of a mistake that I make here, and the mistake is that the tissue is like pretty taut, and it's, you know, the angle, it's hard to tell here, but it's a little perpendicular. I feel a little pop, and I pull back, and I have a large perforation. So, you know, it's only like 35 minutes into the case, so had I not gone to Japan where I had actually seen this happen, I probably would have just put the scope down and hung my head in shame. So, you know, the next, so the options you have are to abort the resection, terminate the procedure entirely, and get a surgical consult, to attempt immediate closure using clips, and then continue the procedure, or just pretend it never happened, and just carry on. Okay, so some recommendations from the literature. So, endoscopic management of colonic perforations after EMR ESD requires identification of the perforation in immediate clipping, that's one opinion. Dr. Cansevoy says when the perforation is diagnosed, attempt to repair the perforation with a few different methods, and then our friends from National Cancer Center say additional submucosal dissection is performed to create space for clipping, and then close the defect, and then continue the procedure. So, I, of course, you always have to listen to your mentors, right? So, you know, you, we chose to continue, just keep calm, and carry on. But, so what happens, this is interesting, right? This is a rectal lesion, and like I'm not very good at this point, especially, and then what we notice is that the anesthesia provider notices that the patient's eye is like really puffing up. So, like air is tracking, like the carbon dioxide is tracking through the retroperitoneal, retroperitoneum, and through the intraperitoneal reflection, and now like the eye is like bulging out with air. So, the patient is developing pneumoperitoneum. So, this is a good example. This is a very famous video. These videos are very hard to find, by the way, of how to deal with pneumoperitoneum. So, this is Dr. Inouye, and what he's done is he's inserted this syringe with a needle. You know, if you have access to these varus needles, these are very helpful, and so the syringe is filled with water, and what they do is you aspirate to get the bubbles. You take out the inner needle, leave the catheter in, and now you have just the syringe. You've attached it to the catheter. You just pull the plunger out, and you can see the air evacuating very nicely. So, that's what we did, and then you want to, again, create space. So, you're going to, at this point, dissect the submucosa. Try not to make this perforation any bigger than it already is. You know, some people might pull out a snare, something like that, you know, try to, you know, get the procedure done quickly, but, you know, we're here to achieve an objective, and we, you know, prefer not to fail. So, you know, you're just kind of working your way through. This is with the insulated tip knife. So, yeah, so the insulated tip knife, so what this allows me to do is stay quite parallel to the muscle, because those perpendicular movements is what will cause these perforations oftentimes. So, it allows me to stay very parallel using the shaft of the knife, I can quickly do dissection. So this is the defect towards the end of the procedure, so it's a little bit larger. I closed the defect, so I sutured this closed, this is the lumen, so everything looks okay. So how do you manage this, right? So most importantly, when this happens, so take a breath, come up with your strategy. You want to dissect the submucosa around so that you do provide space for closure, and you should prevent leakage of intestinal contents, you should suction. This is a great image from a little over 10 years ago now, and this shows that, you know, the different types of perforations, so, you know, if you just get no leak of anything, you know, you can use clips to close, for example, an air leak will lead to pneumoperitoneum, you may need abdominal decompression, you still can close these. Once you start getting fluid and stool, that's where you get peritonitis, and then you're beyond the, you know, closure and the patient being able to go without any other intervention. So it's very important to have a good bowel prep, anyone for ESD in the rectum, it doesn't matter, I always do a full bowel prep, like edemas aren't adequate. CO2 insufflation is a must. These days I'd be surprised if there's a lot of labs left that are not using CO2. Clean perforation, again, not really an issue, it's when there's contamination, and you may need to rotate the patient, but, you know, it's not very easy. And then after the procedure, you would admit the patient, IV fluids, pain control, antibiotics, serial abdominal exams, and, you know, very importantly, you know, imaging may not be necessary if the patient is doing well clinically. So I had a, there's a tendency to treat the imaging, and you'll see this a lot, especially with like upper ESD or POEM or something like that, I'll give you an example. A couple of years ago, I did an upper ESD, resected cancer, the patient was admitted after, and then she like had some like hemoptysis of a small amount. The hospital was covering overnight, couldn't evaluate the patient right away, and they ordered a CT scan, and in the indication, they didn't really mention what was going on, they just said like hemoptysis. So then the ER radiologist reading didn't have time to go through the chart, they're busy, and read this out as a esophageal rupture, Borhov syndrome. So then they called, they didn't, they certainly didn't call me, but they called thoracic surgery, a thoracic surgery intern came in, told the patient that she needed an esophagectomy. I found out about 7.30 in the morning, I went to see the patient in her room, she's sitting up in a chair, and she's crying saying that she needs her esophagus removed. I told her, well, you look fine to me sitting up in a chair without oxygen or anything. So what happens is that, again, so, you know, no one really, you know, kind of follow what was happening in the chart, they didn't realize that, you know, pneumo-media-stinum and things like that aren't uncommon after these type of procedures. So I tend not to get imaging unless the patient has worsening vital signs, or there's some changes in the actual patient. And so, you know, perforations, this is a great study out of National Cancer Center, and basically out of a, you know, 15-year period, they only had 25 perforations. One was a delayed perforation, and one was, you know, during the procedure itself. And so in 15 years, only two patients needed surgery. You know, that's pretty, that's pretty remarkable. There's lots of different closure techniques. There are some cases that, you know, we'll get with, you know, especially in the colon outside the rectum that have been intervened on before that are very scarred down. So now the submucosal plane is not present anymore. The muscle has been fused with the polyp and everything, and some of those situations, you know, you can even do an intentional perforation to get it out, and then close the defect. So that's not uncommon, and I do that from time to time. And so, you know, you'll just put a lot of clips, you know, in an area, I think this is like maybe the ascending colon, and then that could be effectively closed. So here's another example. So ascending colon polyp. So this is, this is like the real deal, like Paris IIc depressed type of lesion. This narrow band, you'll see the center of the lesion, the vascular pattern is not looking great. So I'm going to ask our experts, is this crazy to even try? It looks really like invasive cancer. Definitely looks like invasive cancer, right? So that's what I thought too, but I said, let me just see what it looks like once you inject it. Has it been manipulated before? It's not actually, yeah. So that's away from the lesion, and that here's right, right below this, like, you know, as close to the center, you know, so to speak as you can get, but like, this is lifting like really well, like, so I was a little surprised that this lifted so well. So Dr. Yahagi, what do you think? Do you think it's okay to proceed? Yes, as far as it is diagnostic purpose. Yeah, so I was surprised enough that I thought, why not, let's give it a try. May I comment? Yes, of course. Even if it looks like lifted, maybe the center of the lesion, the muscle is still attached to the lesion. Okay, that's very fair. So, remember, this is in the ascending colon, kind of working the way around, and then, so you know, you can see that, you know, this kind of scar in the center and everything is going to be very difficult to deal with. So we've dissected a lot of it. And then here's, again, is the insulated tip knife. And, you know, I'm trying to get parallel, but I've made a big hole. So again, you know, objective is to, I promise this is not something that happens every day. I mean, it may look like this, but I wanted to illustrate, you know, these cases because they come up not uncommonly. But it's very important to look at the appearance of these lesions. So fortunately, right, we're able to dissect this away and get, you know, most of this out and then be able to complete the procedure. You know, if you really want to be tried and true to ESD, avoid the temptation to get the snare out. And so, you know, we're left with this, you know, I'd say moderate sized hole. But what's good is that, you know, this can be actually easily repaired, even just with clips. We're in the ascending colon. So we're not gonna do anything crazy. Like, you know, I start away from the defect. And what that does is it kind of puckers up the mucosa and then you can approximate it very well. And so these are just standard clips. This is nothing that's like too crazy. This was, this patient did fine. And here's the final pathology. So there was adenocarcinoma with invasion of the submucosa. It's superficially invades the submucosa with a depth of one millimeter, which is 1000 micrometers. No adverse features. So again, going back to our criteria, you know, this effectively meets criteria. So this patient was able to avoid a right hemicolectomy. So this is an example of an upper lesion, fairly small, but again, you know, it's kind of concerning. But the size is really appealing for ESD. And you can see it's in like the distal gastric body on the greater curvature. So this type of lesion is actually excellent for a pocket creation method. So as you kind of work through the lesion, this is the American version of pocket creation method. Okay. So just keep that in mind. So, you know, this is not going to be as good. The, you're going to mark, you're going to make an incision at the proximal border here. It doesn't need to be very big, but just enough that you can start to do some submucosal dissection and then be able to get the endoscope, you know, well beneath the lesion. So the one advantage of the stomach is that, you know, you get a great submucosal lift. We're working our way through really, you know, kind of tunneling underneath the center of the lesion. And then, you know, once you do that, then you could start working your way sideways and then you can work on the mucosa as well. So once you do that, now we have a very nice plane. So now I can get an insulated tip knife if I want to work on the areas around the lesion. And then eventually what you should be able to do is actually just flip the whole lesion over as I worked my way around and then cut the submucosa. And then the lesion is completely resected. So any comments on that? It's really not a seizure. It's suffocating. Yeah, it's a good size lesion for this. And then close it with suture. So I did want to, so this is pretty common too. So there was a, there's a lot of comments on Twitter recently, and we see these a lot, these, these lesions that are really at the anal verge. And these can be challenging, especially because, you know, the hemorrhoidal plexus and all these veins and everything. So I always for these start right at the, at the, at the anal side. And if you're very careful with these vessels, you can coagulate them and avoid, you know, the, the blood bath. So once you get your, your mucosal incision going, then you can kind of open that area up a little bit. And then, you know, you just work your way around. And then to finish, I'm going to use an insulated tip knife, kind of really hugging that muscle and kind of sweeping across until you reach, you know, the other side. You know, it's very important, you know, as you're, as you're starting to kind of track your, your, your rates of, you know, end block resection should be well over 90%, you know, your R0 resection rates, as well as your curative resection rates. And really, you know, evaluate yourself, you know, to make sure that you're meet, you're meeting these outcomes. And also, you know, not tackling on these like really crazy lesions. At first, there's a tendency, you're hungry, you want to do these, you know, wait for the right type of lesions. So this is the end of the procedure. I don't want to take too long, but you know. I think we're going to finish with the question. And one of the virtual audience asked, does anybody ever, ever go into the defect to ensure no injury to peritoneal structures, or intra-abdominal structures, I think, or instill intra-abdominal antibiotics? Definitely IV antibiotics, but I wouldn't be exploring, you know, the peritoneum, so. Yeah, I don't think it's a commonly done. Yes. Just a comment on your last ASD video. For the anal verge lesions, do you do any injection of lidocaine for your lifting solution because of the post-procedure pain the patient might feel afterwards? So surprisingly, they don't feel too much pain. I do tend to suture a lot of these at the end, and they will feel this like kind of like pulling sensation. They'll feel the need to like urinate and things like that, but it actually gets better after a few hours. So I don't, I don't know if the others do. Yeah, if you're involved in the anal canal, the pain can be really severe. So I typically do after resection application of lidocaine. I think Japanese experts does the injection solution mixed with the lidocaine. I usually inject 1% lidocaine as a sub-mucosal injection at the anal verge, then start mucosal incision and sub-mucosal dissection. But the post-procedure pain is minimal. We don't have to worry about it. Yes, I also use lidocaine just because I perform the procedure with conscious sedation. Oh, okay. I think you're very gentle. All right, thank you very much. Thank you.

endoscopic submucosal dissection

R0 resection

curative resections

rectum

colorectal ESD

complications of ESD

management strategies