It's my pleasure to now invite Dr. Arvind Trinidad, who's going to speak to us on ablation therapy for Barrett's esophagus. Thank you, Felice. Thank you to the course directors for putting on such a wonderful course. So Ken just went through basically the resection of endoscopically visible vessels. But the goal of Barrett's neoplasia is really to eradicate all Barrett's. So after you resect with ESD or EMR, you want to ablate the remaining Barrett's because it's a field defect that's going on microscopically. So I'm going to talk about ablation therapy. These are my disclosures. So this is a figure from a paper we submitted. It's not yet published. But you can see here that ablation therapy, or Barrett's therapy in general, is a disruptive technology. This is a graph here. I'll put the pointer on. But in the purple here, you could see is esophagectomy. This on the x-axis is the years from 2006 to 2015. And you could see as we've been implementing endoscopic eradication therapy for Barrett's, the amount of esophagectomy that we've been doing has dramatically gone down. So it's really, you take a step back, you could see this therapy is working. It's really disruptive technology. And we're seeing good outcomes. So this data here is mainly for RFA. But you can see the effect that ablation has on the natural history of esophageal adenocarcinoma. And here is rates of progression to cancer if you don't perform any therapy. And this is on the second column, if you perform ablation therapy. And you can see, not surprisingly, in nondysplastic Barrett's esophagus, the rate doesn't go down all that much. For low-grade dysplasia, you go from 1.7% to 0.16%. And high-grade dysplasia, not surprisingly, you go from around 6.6% to 1.7%. So again, ablation therapy is really having a great effect here. So this figure comes from the recent guidelines that Prasad was on in terms of who do we ablate, who do we not ablate. So patients with nondysplastic Barrett's esophagus, we do not ablate. There are some special circumstances, but I won't talk about that today. You want to make sure that your pathology is reviewed by an expert pathologist. So if you're a smaller institution, consider a consultation to a bigger institution that sees a lot of Barrett's pathology. If you have low-grade dysplasia after a confirmation, there's actually one of two modalities. You don't have to go with ablation. It's actually OK to survey. Where I practice, most patients want ablation therapy. In the United States, we're not 100% sure what the right path is, and Satyamwani and colleagues are actually leading a trial called the Servant Trial that will help answer this question. For high-grade dysplasia after resection of visible lesions or lesions seen on MBI, then it's appropriate to perform ablation therapy. After achieving complete eradication of intestinal metaplasia, then you survey every 3, 6, 12 months and then annually afterwards. The baseline pathology is low-grade dysplasia. It's one year after, three, and then every three years, and then every two years, I guess. Yeah, that's what it says. For if you eradicate a T1B lesion and it has low-grade features on it, meaning it's well-differentiated, there's no lymphobascular invasion, it may be OK to proceed with ablation therapy. However, there really should be a multidisciplinary discussion with your surgeons. So our endoscopic toolbox has increased dramatically since for 2007 to 2022, and that's partially the reason why we have such good outcomes, and I'll talk about what we have today. So the first therapy we have is radiofrequency ablation. There is very good evidence for that, which I'll show. It's basically heat therapy. You have tightly spaced electrodes. It's a proven preset of energy and power densities. The generator will really turn off at a preset determined level resistance, and so overall it's pretty safe, and we don't see that many adverse events with it. This is what the technology looks like. You have these catheters here that connect to a generator. With the Halo360, which will ablate circumferentially, and I'll show a video what that looks like in a second, you basically pass a wire into the stomach, and you pass this catheter over the wire, and then endoscopically, you can see what the catheter is doing. These focal ablation catheters attach to the endoscope, and you could treat, it's basically touch-up or paddle treatment where you could treat lower amounts of Barrett's esophagus, and I'll show a video of that too. So this is just a cartoon of what this looks like. With the 360, you pass that catheter over a wire into the esophagus, and you inflate the balloon, and you treat in a 360 fashion, and if you don't have a lot of Barrett's or you're bringing them back for subsequent treatments, and you have smaller amounts, you could use these paddle catheters that will ablate these Barrett's. So on the video on the left will be a video where we see a pretty decent amount of Barrett's, about three centimeters, and this is where we're going to use the 360 Halo catheter. It's very, very important that you do a very detailed exam, so on high definition white light and MBI, take a good look. If you see any raised lesions or suspicious areas, it's okay to go back to EMR and take that out again. So here I am passing a wire into the stomach, and then I withdraw the scope, and so you have a wire hanging out of the mouth. And then what you'll see in a second is that we'll pass the Halo 360 Express catheter along the wire. I like to use a 450 stiff jag wire as opposed to the wire that comes with the apparatus. I think it's a little stiffer and easier to pass the catheter down. And then endoscopically, you visualize what you're ablating, you inflate the balloon, and then treat the Barrett's. It's very easy to use. I think a lot of this technology is moving into outpatient centers or community centers just given the ease of use of it. And here you can see a nice ablation effect. In the video on the right will be the paddle catheters or the focal ablation therapy. This is actually a patient who's treatment naive, but given the small amount of Barrett's, dysplastic Barrett's that was there, actually chose to use a Halo 90 catheter. And you'll see in a second. So what I like to do is treat circumferentially first at the G-junction. I think that's important because a lot of recurrences tend to happen at the gastric cardia, the top of the gastric fold. So I think it's important to treat that. And then after that's treated in a 360 fashion, then I proceed a little more approximately. And I'm going to fast forward this. And then with the focal catheters, you treat twice, you scrape, and then you treat again. So this is a nice study done by Nick Shaheen. It's a level one evidence showing that this works. So it was a randomized study of 127 patients with high-grade dysplasia and low-grade dysplasia at 19 U.S. medical centers. And you could see here, you know, patients responded very well in terms of complete eradication of intestinal menoplasia or complete eradication of dysplasia, whether it's low-grade or high-grade, this technology works. This was a SIRF trial that Prasad briefly mentioned in his talk. This was a Dutch study for low-grade dysplasia. And they found very similar outcomes versus a sham group. And they found that using the use of radiofrequency ablation prevented progression to high-grade dysplasia or cancer. You know, this population here, just a note of caution, they progressed in the sham group pretty aggressively. I don't think we tend to see that in the United States. And again, another reason for the SIRF in trial that Satya Malani and colleagues are leading. So what about cryotherapy? I know a lot of you have been hearing about it. I do a lot of cryotherapy in my practice. The guidelines recently recommended it for RFA refractory disease. A lot of people use it for nodular disease not amenable to resection or surgery. I'd buy some caution in that. But, you know, it can be used for that. With advanced techniques like ESD, usually most nodular lesions can be removed. And then for primary therapy, you know, post-resection, sometimes of intramucosal cancer of T1B, cryotherapy could ablate a little bit deeper into the submucosa, so some people use it for that. And then we'll talk about decreased pain tolerance as well. So the first modality we have is liquid nitrogen cryotherapy. Here you can see here it has this console here where behind this door would be a big tank of liquid nitrogen. This will attach to a catheter that goes down the endoscope. And it's a non-contact spray. It's a 7 French catheter, so it could go down a regular gastroscope. There is a need for a decompression tube. There's a 20 French and a 16 French. The 20 French is a little bit bigger, but a little bit more durable. The 16 French is a little bit smaller, but it could bend very easily. And the point of that is to basically suck up excess gas in the stomach to prevent perforations. So let me show you a video of this. So it's pretty neat technology. It's a non-contact spray, and you can see it's spraying abnormal areas of the parrots. The decompression tubes can sometimes be a little bit cumbersome. And then the dosimetry is such that you spray, you wait 20 seconds for this to de-thaw, and then you spray again. But overall, retrospective studies have shown pretty good efficacy. This is probably a newer system. It's a C2 cryo-balloon ablation system. Instead of liquid nitrogen, it uses nitrous oxide. So you have this handheld controller where a catheter attaches to. It's a 3.6 millimeter diameter balloon catheter. It goes down a therapeutic scope. And this balloon inflates, and what's nice about this is that the nitrous oxide is sprayed from a diffuser where the balloon is touching the esophagus, and then you get an ablation effect in that regard. It's a self-bending system, so there's no need for a decompression tube. And these little capsules that go in the controller contain the nitrous oxide. I'll show two videos. There's a focal balloon and then something called the standard 90. So with the focal balloon, you inflate the balloon, and it's basically treating the area that you direct the diffuser at. In order to treat above or below, you have to reposition the balloon. So that's why there's the standard 90 and the soon-to-be standard 180 balloon, which actually you could, when you push the foot pedal, the balloon actually automatically will go up while it treats. So it's meant for longer, greater distances or greater amounts of air. It's similar to the Halo 360 Express. This was a multifocal, sorry, multicenter prospective single-arm study published by many people in this room. And they basically looked at 120 patients, patients who had high-grade dysplasia or intramucosal cancer, and they found that per protocol, effect was for complete eradication of intestinal mitoplasia and dysplasia was very high at 97% and 91%. So this technology also works pretty well. So one of the benefits of cryotherapy is actually pain tolerance. And so some of you may see that a lot of your patients with RFA actually complain of pain afterwards. It requires a cocktail of Tylenol or codeine or other therapies. And so this was actually a prospective study that our group did it at Northwell along with Shivagni at Rochester and the group at VCU. And we actually looked at pain scores for patients receiving RFA and cryotherapy. And you can see here, these were baseline pain scores. And then this is post-treatment. The blue would be the cryotherapy group. The yellow here would be the RFA group, but with the paddle treatment. And the red would be the RFA group with circumferential treatment. And you can see here clearly that post-treatment, the RFA group, both circumferential, had the highest pain scores post-treatment and at 48 hours. And the cryotherapy group had very little pain compared to the RFA group. So if patients can't tolerate the RFA, clearly this shows that cryotherapy is an option. The same effect was also shown for the cryo-balloon group as well. This was a study done by the Dutch group and basically found the same thing. Post-procedure, the cryo-balloon group basically had pain for about two days afterwards. The RFA group, the pain lasted as much as 14 days after. And in terms of regression of Barrett's, they found that both treatments, RFA and cryo-balloon, were equally effective. So there's a third treatment called hybrid APC that has recently come out that people have been using. So with regular APC, if you were to treat Barrett's esophagus, it's not very effective. But if you have a submucosal injection, you're able to treat at higher wattages, which is we traditionally wouldn't use with APC. It's a cheaper alternative. As you probably saw, a lot of the technologies that I showed you require a generator. This doesn't require an expensive generator. There was a randomized, actually it's not a randomized study, it's a prospective multicenter study from the Dutch group that this was done in patients who were treatment-naive. And in combination with EMR, they found that hybrid APC was also very effective, both for complete eradication of intestinal menopausia and dysplasia. What we looked at at Northwell was we use this technology a lot for RFA or cryorefractory disease. And we published this case series looking at patients who had failed both RFA and cryotherapy. And you can see here, all these patients were a long segment. They all received multiple treatments of RFA or cryotherapy. And they all had significant residual Barrett's esophagus. And we employed hybrid APC for these patients. And I'll show you a video of one of these patients in this case series. And hybrid APC was actually very effective in eradicating the Barrett's esophagus. So this is a patient with long segment Barrett's after many treatments of radiofrequency ablation and cryotherapy. You can see here, this is using the hybrid APC probe to make a submucosal injection. And this does look like a long segment of Barrett's. And it can be tedious at times. But after you get into the groove of the treatment and before you know it, the segment's actually ablated. But you can see here, after the submucosal injection, I'm treating here with hybrid APC. The most important thing when you're first starting this technique is to make sure you're pressing the right pedal and you're not trying to... When you're trying to inject, you're not ablating. Because if you're ablating at high wattages without the injection, that could cause a perforation. If I fast forward here a little bit. And so that's what it looks like when it's done. Surprisingly, the patients don't have much pain. I've used this technology a lot for refractory disease. And patients really don't complain of pain after this. So in conclusion, endoscopic eradication therapy for dysplastic disease is effective. It's really important to resect nodular disease first and then use the ablation therapy to only ablate flat disease. Compared to 10 years ago, we have many, many tools in the toolbox, as I showed today. And there's more on the horizon that we'll hear about soon. Thank you very much for your kind attention. Thank you.

ablation therapy

Barrett's esophagus

radiofrequency ablation

cryotherapy

hybrid argon plasma coagulation