Building on that, I will dive a little bit deeper into EMR and ESD in this next lecture. And because we are a little bit behind time, I'm going to go a little faster with this one than with the previous one. So with that, let's see here, you've seen the disclosures. The objectives here really are to talk about EMR and ESD and kind of differentiate them in the GI tract interventions best we can, as it kind of pertains to the American context. Remember that a lot of the resection paradigm started in Japan and then in the Far East, and we've kind of caught on to it in the last 10 to 15 years. And so I'll speak a little bit more to it from our perspective. So like everything else, particularly in this course, we've got to figure out what's really relevant to the APP perspective. I think a lot of endoscopy principles we've spoken to, there's a lot of collaborative elements. But in this particular realm, when you're talking about EMR and ESD for primarily for precancerous and cancerous disease states, where does the APP fit? I think the most important questions really are these, which is as to when you're in clinic, when you're doing any inpatient or other consult, taking phone calls, referrals, really get an understanding of which are the best patients that are suitable for these procedures. Next question is what is the appropriate and optimal prep involved in this patient population and what will position the patient the best for the endoscopist and the endoscopy team on the day of the procedure? Next big question is what are the likely complications from mild, moderate to severe that could emerge from these procedures in the intra-procedural timeframe, immediate post-procedure, and then 24 hours to up to 30 days out. So that's important. And that we'll talk about. And then of course, what is the short and long-term follow-up, particularly because these patients are those that harbor cancer at various stages and require expedited care and interdisciplinary care coordination, some of which I referred to in my previous talks. So these are largely the indications for EMR and ESD. I'll try to make this simple. Pretty much any lesion that's less than two centimeters in size is up for grabs for EMR pretty much anywhere in the GI tract, give or take. So less than typically one centimeter, between one and two, we can go either way, but anything that's less than two centimeters that's superficial, that's not invasive, not ugly looking, is amenable, accessible to the EMR devices and scopes is good for EMR. Anything that gets really big, that gets more laterally spreading, like dysplasia and IBD, early gastric cancer, larger lesions in the rectum, they are really ideal candidates for ESD, not only because the pathologist really prefers a larger specimen to be presented as one unique entity, but also the risk for invasive disease goes up and you get a better assessment for the stage of the tumor or neoplasia in that case. So larger lesions, think ESD, and that's the message of the slide. The EMR techniques were really developed around polypectomy in this side of the world. Here is an injection of the polyp, a snare looping around it, squeezing tight, and then using cautery, or nowadays actually doing it cold as well. So the EMR technique is well defined in this graphic for the colonic situation. And sometimes we will use this in the duodenum as well, sometimes in the stomach as well, less often in the esophagus where we have some other techniques for EMR, which I will get into real quick here. So this particular video you have already seen. I showed you this polyp for EMR in the colon. This was a cirrhotic patient. In this particular case, we used all the techniques of injection and dye and prophylactic closure and all of that stuff. But you've already seen this video, so I'll move on. Now, this is the esophageal EMR construct that I was telling you about. So if you watch here, there's a marking around the lesion, and then we have this band apparatus, which we also use for variceal band ligation for bleeders. We suck up the lesion and we put a rubber band around it and create what we call a pseudopolyp. And with the pseudopolyp now made, you can see the black rubber band in a second here, hopefully right there. Hopefully it projects well. And then we have a dedicated snare that passes through this plastic barrel here. And then we can cut above the band or below the band, it doesn't matter. And we have a fairly decent-sized specimen come out for pathology. From this point on, if this is superficial disease limited to the mucosa, we are good to go. If there is invasive cancer, then we need to move on to non-endoscopic evaluations because the risk for lymph node metastases goes up. Another type of esophageal or foregut EMR is this CAP-assisted EMR, where we can tackle larger lesions. Unfortunately, I'm told this CAP is now no longer in practice, has been withdrawn by the company. But it used to be a neat procedure where we put a snare around the barrel here, suck the lesion in, and we can get really large hunks of tissue, almost ESD-level tissue, depending on the size, either on block or at the most two pieces. You can see here the size of the defect is much more significant. And similarly, the risk for perforation is even more than the band approach. But at this point, I'm told this is over. And this was a neat procedure that I had the chance to practice for many years. And you can see the size of the lesion here. And the base, of course, as you can see here with the muscle layer, and a little bit more of the lesion to go. Nowadays, this would typically be carried with ESD. So ESD is a little bit more advanced. Similar thing, you have a larger lesion, injection of fluid under the lesion, raise the lesion. And then as I showed you in my previous talk, you take one of these fancy knives, anywhere between $600 to $1,500. And then you cut it out, basically carve it out, and then present it as a single block of tissue. This is a typical ESD video. You examine the lesion. You got some depression going on there in the middle. There may be some invasion. This could be a patient who could actually have invasive cancer. And here we have a hook knife, just because it's shaped like a hook. And you start dissecting it well outside the margins of the lesion. Get inside the space and continue dissecting it, very similar to what Caitlin showed you for POM. And then get it off. So a little bit more involved, takes a lot of training, a lot of skill, time, anesthesia, and so forth. So here are the efficacy rates. And I'd like you to focus basically between EMR and ESD, the curative resection rate, which is the surgical term known as R0 resection. So that's one area where ESD really wins hands down, is if you have larger lesions, you're more likely to get a negative margin and a complete resection going. But by the same token, you get what you pay for, right? So you are doing a more advanced procedure, more risk. You typically go deeper. And you use more sharper instruments in the moment. So your perforation rates go up. And these do vary from practice to practice and from paper to paper. But suffice it to say that everybody agrees that the perforation rate is the one distinguishing feature on the adverse event side. And the curative resection rate is the one distinguishing feature on the positive side that distinguishes these two procedures. So that's an important slide to keep in mind. Obviously, when we get into these procedures, there is no substitute for a detailed history and physical. This is really, really important. This is why most of these patients need to be seen in clinic, whether it's telemedicine or in person. And these are the reasons why we need to see them first. We need to really assess their risk, make sure that this would be the right procedure for them, and obviously manage the pre-procedure stuff, as we discussed many times today already. But the informed consent is really important, because these patients could end up in surgery from a complication or they could have an aborted procedure if there is invasive cancer found or some other outcome that you may not have imagined. So they may prefer surgery. And many of these cases are borderline. They could very well have gone to surgery as well, especially if you don't have a very high quality and experienced EMR and ESD teams in the building. So informed consent is very important. In this particular realm, I feel that alternatives to the procedure are really important. Just because you can do ESDs and EMRs doesn't mean that you should be doing them in every patient, regardless and indiscriminately. I think if a surgical outcome is expected to be better, then I think the patient should be routed to surgery. And that's what the best teams in the world do. And that's what I like to teach as well. Technical considerations are beyond the scope of typical APP practice. But here are those which you should be aware of. Obviously, bleeding risk relates directly to pre-op procedure prep. What type of sedation? Well, mostly in America right now, for whether it's upper GI tract or lower GI tract, most of these patients will at least get MAC. And some of these, especially when you're working higher up in the esophagus, will get a tube anesthesia as well. A little bit further into the specific organ areas, this is EMR in Barrett's, which is a very well-established technique. Endoscopic resection of focal raised lesions is actually on the GI boards for the fellows as well. This is a raised lesion that has a higher than average probability of harboring cancer. So this should be taken out with EMR. But there are still some recurrence rates here long-term that are listed here up to 10% if you don't do a complete job in the first instance. ESD in Barrett's is becoming more common now. Again, this is more applicable for squamous cell cancer, which tends to be a little bit more laterally spreading for larger adenocarcinoma or high-grade dysplasia lesions. And that's where also I think it becomes important to do an EUS imaging. And if you have a carcinoma diagnosis on biopsy coming in for EMR or ESD, it is our typical practice to do a PET CT before because about 10% of stage one esophageal cancers will have a remote metastatic focus. And that's been well-described. So if somebody has a bone lesion or a liver lesion, you really shouldn't be doing an EMR or ESD. And every so often you'll run into one of these situations. So EUS and PET scan typically is the pre-op imaging algorithm. Pre-resection imaging algorithm, if I should say that. This is ESD for Barrett's large lesion. You can see fairly large over here and then resected and then presented on a foam pad to the pathologist. So basically, short of having another six inches of esophagus, the pathologist wouldn't know any different. He has the entire tumor here and he'll deal with it pretty much as an esophagectomy specimen minus the lymph nodes. So major advance there. Here is a relatively recent paper for EMR versus ESD. There was no real difference in complete remission. At three months, it was a short follow-up, but severe adverse events were more significant with ESD than with EMR, which is understandable. This conclusion here was that EMR may be less likely to achieve curative resection, but at the same time presents similar pathology with lower adverse events. Short study, but one of the important studies in this space. As I mentioned earlier, gastric cancer was the main indication for ESD in Japan and it remains an indication for EMR and ESD in this country. For smaller lesions, we will go with EMR and for larger lesions, we will go with ESD. The five-year survival for well-selected, good biology patients is pretty close to surgery, but that's the key. Which is the patient you're taking? What is the size of the lesion? What is the tumor biology? And who's doing the operation? This 100% is not universally achievable if you are not careful with all of those criteria. So here is a typical example of ESD for gastric cancer, kind of a scarred down lesion, and then you have to go all the way around and take this out. This type of a case typically would take anywhere between three to four hours for even moderately skilled endoscopists. The Japanese can probably do it much faster. This is another paper looking at ESD versus EMR for gastric cancer. Again, the message here is ESD had a lower risk for local recurrence, that's understandable, but similar risk for bleeding and the on-block resection rates were much higher. This was a meta-analysis of 6,000 patients, so an important study to keep in mind in the British Medical Journal from 2019. Now in the colon, which has been an area of debate, this is typically the kind of lesion in the colon, colorectum, so to speak, which would be a very good candidate for ESD. It's kind of lobulated, it's kind of granular looking, laterally spreading, kind of all over the place. One snare will not be able to get this all, so this would be a good candidate for ESD. And as you can see here, very nicely depicted, this lesion has been carved out pretty much like a piece of meat here and presented to the pathologist in one block as a oncologic specimen, as you can see here. So this is an absolutely perfect indication for ESD, even in the Americas, and it's being done fairly regularly and actually quite safe because the rectal wall is much more forgiving than the duodenal wall or even the esophageal wall for that matter. So when people are starting out ESD, they typically will choose these lesions in the rectum, you know, go inside a room with their team and stay there for two or three hours to do this case and then come out victorious most of the time. So ESD will allow resection when EMR is not possible. This is an example of a scarred down lesion. Previous attempts, fibrosis, tattoo injections, whatever the case may be, you can dive a little bit deeper. Even if you have a small perforation, we have the tools nowadays to close them with endoclips and not have to go to surgery. So efficacy of EMR and ESD in large colorectal lesions is on this slide. Again, you know, it's a lot of patients here, a lot of polyps. Recurrence was found in endoscopic surveillance only in about 13 to 14% of patients, and the clinical success with endoscopic resection was fairly high. So I think, again, if the case selection is good, your skill set is good, this represents a very nice alternative to hemicolectomy or subtotal colectomy, depending on the case. And again, it requires competency, skill assess, skill building, teamwork, appropriate selection of the patient to get these types of outcomes, but it is possible. This is another paper looking at 13,000 patients, 90 plus percent curative resection for ESD, perforation rates around 4%, but many of these are manageable endoscopically, especially if they're recognized in the procedure. The key to perforation management is how quickly around the procedure do you recognize it. Most that are recognized in the procedure, they do very well. Those that are recognized in the recovery room still do well. Those that go home are unrecognized and come back two days later are the ones that don't. All right, immediate follow-up. This is again where the APP role becomes important. The endoscopist has finished the procedure. If you're admitting this patient overnight, typically a nurse is involved, a trainee might be involved, an academic institution. APPs are notified whether they're inpatient or part of their practice. They need to know this patient's coming in and what to watch out for, especially if they're covering the late shift and or handing off to the overnight team. Then of course, I have always encouraged APPs to be part of the tumor board discussion. These patients will go for pathology review, for surgical review. Here we want to see if the specimen is of good quality. Was it completely dissected? Were the margins clean? What was the level of invasion? Was there any lymph node involvement? Finally, my favorite here is the tumor biology. Anytime you see a dissected specimen, regardless of how good a job you've done, if you see the words poorly differentiated, be very, very careful. Poorly differentiated tumors kind of have a life of their own and they march along a different tune. They are invariably, you're better served by bringing these patients to somebody else's attention to make sure that endoscopic management was really only required and that there's not much more required. Because especially in a young, surgically fit patient, when you're dealing, especially in a syndromic setting such as Lynch syndrome and other FAP and such, dealing with a poorly differentiated tumor, you want to make sure that every other alternative treatment option has been exhausted before you take on the burden of managing this patient alone for the rest of their lives. Because this is a very high likelihood of recurrence in these patients, especially if there are borderline resection cases. The multidisciplinary tumor board is very, very important. Why, who, and when? Well, anytime you have submucosal invasion, it is still in the guidelines and in best practice to bring this patient to a larger group of providers to ask the basic questions. Did we do a good enough job? What's this patient's risk of coming back with cancer? What else do we need to do? And so on and so forth, including if you're doing endoscopic surveillance, when should this patient come back and how often? And when should cross-sectional imaging be thrown in? These are highly, highly educational events. In our case, they occur every Friday morning. So every time you have a chance to attend these virtually or in person, the virtual option is almost always there. And it's your patient. I encourage you to go and listen to this discussion. The latest guidelines are referred to there, and especially an entity known as the NCCN, the National Comprehensive Cancer Network Guidelines, which is the final word in cancer care in America. It should be in the world as well. Those guidelines are referred to, and everything proceeds along those lines and along the lines of any new research that might have emerged. So consensus-based decisions, especially in high-risk individuals, is decided here, and it behooves us to bring these patients to these congregations as often as we need to. There are still some very distinct indications for surgery. I kind of alluded to them earlier. Again, you see my friend, poorly differentiated tumors, especially with incomplete or borderline resections, lymphovascular invasion, positive margin resections, and anything that you are not sure that you have completely removed or that you can completely, safely follow endoscopically. I had recently a patient that had a sigmoid diverticular disease and had a relatively straightforward lesion in between the diverticulae, which I thought I had removed fairly well, but he was 50 years of age, and by the time I was done with that colonic segment, I couldn't even tell normal from abnormal. So I called our surgical colleagues, and I said, he's a 50-year-old guy. There's no way in hell I will, and he came back with a high-grade dysplasia of the pathology, by the way, and I said, listen, you know, just take the sigmoid out, and we are done, and the surgeon agreed. It is not a failure of endoscopic therapy, but it's smart decision-making in the interest of the patient is what we felt. Managing complications is another favorite area of mine. As I said, in this realm, the quicker you pick up the complication, the faster you anticipate them, the vigilance that you keep in the procedures and around the procedure, and that takes the whole team, the better the patient outcome. So again, collaboration with services, timing of imaging, lab workup, updating lab workup. I have a patient today with post-TRC-P pancreatitis that we are managing at another hospital, and I'm getting labs at three o'clock, four o'clock my time, so that we can go into Friday night with a plan for the weekend, and then, of course, very, very important, documentation of events and plans, and a lot of the times, I will have my APP kind of, you know, document as I move on to another task that I need to finish before the end of the day, and then he or she will document that on my behalf that we did this, we did that, we called upon this, and we engaged with this, and so on and so forth. It still, unfortunately, is true that if it didn't document, it didn't happen, and that's an unfortunate reality of our lives. Long-term follow-up is mainly based on surveillance strategies, timing, frequency, the nature of surveillance, and always guideline-based therapy, and where there is not a guideline-based management, you go with expert consensus and best practice. Long-term follow-up is where the rub is in cancer care, so a lot of the studies you'll see will be relatively short-term follow-up, but the real durability test of an endoscopic intervention is borne out at the 5-year and 10-year mark, and those are the interventions that have stood the test of time. Everything else kind of falls apart, so these are those recommendations. These guidelines are available to you. These are very recent, and pretty much every society has an update on this as well. Practice pulse, I think for the APP in the realm of endoscopic resection, the cognitive clinical assessment of the appropriate patient coming into the referral pathway is very important, and this is largely looked at in the clinics when you work together with the physician, and then the pre-procedure testing and optimization, which has been already discussed a lot today, is really critical, and you guys will help us a lot with that as well. The follow-up is key because of biopsy results, complication management, surveillance interval timing and scheduling, and then, of course, all along we have the interdisciplinary coordination and so forth, so very, very critical elements for APPs to dive into. With that, we go to the poll in question one, which is the following. Is a key advantage of EMR over ESD? Advantage of EMR over ESD. ESD is less technically challenging or faster. ESD allows for larger…sorry, advantage of ESD over EMR. ESD allows for larger, more complex lesions to be removed in one piece. ESD has a lower risk of perforation compared to EMR. ESD does not require semi-causal injection for fluid. So, let's see what the group feels at the late-afternoon time frame. So, key advantage, we're at 91 percent, so I'm maintaining at least 190 percent every session. That's great. Fantastic. All the other options are wrong and absolutely correct. The ESD allows for larger pieces, larger tumors in one go. And the second question, which of the following is the most common complication of both EMR and ESD? Most common. Pneumothorax, cardiac arrhythmias, renal failure, or bleeding? This should be easy. 100! All right, that's it. That is the all-time record. And Dr. Tiwani, sorry, but now we can go into questions. Let's see. We go back to Caitlin or Sumit, or how do we? We have till four o'clock, I think. We're combining break and questions here, I think.

EMR

ESD

GI tract interventions

tumor biology

multidisciplinary discussions

guideline-based follow-up