Good morning, my name is Mark Benson, I'm one of the interventional endoscopists at the University of Wisconsin. And yes, we're going to talk about advanced lesions or fixed lesions, which can be a challenge. So I have nothing to disclose. We'll talk about basically three techniques to remove these fibrotic lesions. We're going to talk about cap-assisted avulsion, talk about a catheter called endorotor, and then hop biopsy avulsion, which I actually like. So this is the ultimate fibrotic colon. So earlier this year, at the University of Wisconsin, they had an art contest. And the theme of the art contest was art and science. And it was like open to the whole campus. So it was like faculty and students, and you were supposed to create a piece of art that was going to convey some aspect of science. And I was out running one day, and I'm a woodworker, and I was like, well, I guess I can make a colon, I guess. And you know, if you look at anything on the internet, so if you look at a picture of anything on the internet, you plug in like glass bird, you'll see 50 pictures of different birds made out of glass, like hummingbirds and pelicans. And so a few days later, I was just curious. So I looked on the internet, I put in wood colon, came up with zero. So then I was like, well, I got to make this thing, because it could be potentially the first of its kind. So I did. I set out making it, took me six weeks, working daily. It's made out of 226 pieces of wood of different species. It's supposed to represent the microbiome. I know that's nerdy, but I got third place, which I was pretty happy with. My colleagues feel like I was robbed, they feel like, what could be to wood colon? But I was beat by two other artists. I got asked to display this somewhere in the department. I said, no, I kept it, because I have three teenage kids, and I assume this is going to be a family heirloom one day that they're going to fight over. It's my legacy. So we're talking about fixed lesions or fibrotic lesions, and they're a challenge to remove, right? So this occurs in the setting of submucosal fibrosis, and that leads to a non-lifting area. So it's a challenge to remove these endoscopically. It usually occurs in the wake of prior manipulation, that is, prior attempts at resecting these areas. As we talked about earlier this morning, tattoo placement itself can cause this submucosal fibrosis. Like, I'll get reports for resection of acecal polyps, and I'll read the report, and they'll say, tattoo placed at the lesion. And it just is difficult, then, I know, going in there, that it potentially could be a fibrotic area. Sometimes in the setting of chronic inflammation, like an IBD, you'll see submucosal fibrosis. I see this frequently in the rectosigmoid colon, where you get prolapse of those polyps, and that leads to a fibrotic area. And those can be a challenge. It can be a big fibrotic area that you have to try to remove. You can see it often in the setting of recurrent adenoma, and what we talked about earlier this morning, really important to recognize if you feel like there's a malignant invasion of that polyp. You should not try to resect that with these techniques. Having a fibrotic lesion is a known risk factor for incomplete resection. So CAP-assisted avulsion has been around since 1990, and it was first used to basically resect esophageal lesions. And the technique has changed over the subsequent decades. But basically, it entails lifting the polyp with a submucosal injection and trying to raise it up, using a transparent cap off the end of the endoscope or colonoscope and sucking up some of that mucosa, and then using a snare to resect that, and ideally, you want to resect it on block. Here's an image of the... So this is a recurrent adenoma in the ascending colon. Again, you want to try to raise it up. Often, it sometimes won't raise because you have a fibrotic area. You want a thorough inspection to make sure that you don't feel like it's a malignant invasion. And then you take the cap on the fibrotic area itself, and you try to suction up that area, up into the cap itself. You want to use a stiff snare here. And close the snare on the resected area that you want to remove. And then you can often inspect the area to see what you've grabbed. It's difficult sometimes because you have a little bit of a limited field of view. Once you feel that's safe and you've resected the fibrotic area, you ligate it. You can use this technique in a piecemeal fashion as well. You do want to inspect for muscle injury or perforation after you resect these specimens. And then you close on the tissue. I often pull it up away from the empty layer. And then you'll basically examine the muscle layer to look for any more adenoma or any neural injury. So, this is a recent study using this technique to remove fibrotic areas. It's a multi-center perspective cohort study on 70 fibrotic lesions. The mean polyp size was 2.5 centimeters, and the mean fibrotic area was a centimeter and a half. So, that's where this technique is helpful, when you have a larger fibrotic area that you need to remove. They did a follow-up colonoscopy in about six months after they attempted these resections. Basically, they had these 70 lesions, two of them they couldn't remove because there was malignant invasion. They could use this technique, this CAP-assisted avulsion, for most of the polyps. This is incorrect in their table. This number there should be about 20 percent, but the point of this showing the slides, they had about 20 percent recurrence rate when they used this technique. You can use adjunctive therapies, like hot biopsy forcep avulsion, or the snare tip, to remove, to destroy residual adenoma. They also had a recurrence of about 20 percent on the follow-up colonoscopies. But they had basically 97 percent complete initial resection rates, 20 percent rate of recurrence when they did the follow-up examination. They had neural injury occur in about 9 percent of patients. They had one transmural perforation in this study, and they had delayed bleeding occurring about 9 percent of the time. All of the muscle injuries here were treated through the scope clips. None of the patients in this study had to go to surgery. This is an older study showing this technique to remove large flat polyps. They looked at 124 colon polyps. The mean diameter, again, was about two and a half centimeters. They had a 91 percent complete eradication rate. They had a 10 percent complication for this study, 4 percent perforation rate. Two of these patients in this study had to go to surgery, and then bleeding rate about 6 percent. The reason why I show this study is because this is an older study, and so this technique has changed over the last decade. So in that picture on the right, you can see the cap is extending off the colonoscope by some distance. And so that's been the change in the evolution of this technique. So you actually just want to have that transparent cap coming off the endoscope by about three or four millimeters. That way, it kind of restricts how much mucosa gets sucked up into the cap, so you're not sucking up a big section of MP layer and doing a perforation. What I liked about this study is that you can learn this technique. This endoscopist basically broke up their experience in quartiles, and they found that their overall complication rate went down, and their resection rates went up. So you can learn this technique with minimal additional equipment to your endoscopy unit. Next thing I'm going to talk about is endorotor. So this is a catheter. This is basically a single-use catheter that's made out of metal that goes through an endoscope or colonoscope. It basically has an inner cannula that spins, and it rotates at either 1,000 RPM or 1,700 RPM. It's recommended to use the higher RPM. And basically, it has a beveled tip that has some suction. So you place this device on the fibrotic area, and it sucks up the mucosa and basically resects it. And as it's sucking up that tissue, the tissue goes up through the catheter, and it's collected in a filter on the unit itself. And then that specimen can be sent off to pathology for analysis. It's developed from instruments used in otolaryngology and orthopedics. The device doesn't cause a lot of tissue destruction if it's just spinning in the colon without or spinning in the GI system without suction. Here's an image of the technique. So the inner cannula spins clockwise. So you do want to basically slowly work your way across these fibrotic areas from a left-to-right fashion is what's recommended. So this is basically a polyp that does not lift. You'll see that there'll be some intraprocedural bleeding. So they're saying that it's recommended that you use a little bit of epinephrine when you're raising this up to mitigate that bleeding to help clear the field so you can see what you're resecting. The catheter itself has a solid black line that's located 180 degrees across from the bevel, so you know that the beveled area is basically opposite of the black line. The area that gets resected is about 3 millimeters squared, so you have a very small area that's getting resected at one time. The dashed lines on the side tell you that basically the bevel at the tip of the catheter is 90 degrees to that. Later on in the video, you'll see that it shows a good example of how the tissue gets basically sucked up into the actual catheter itself. You can change the level of suction depending on the fibrotic area that you need to remove, like if it's not getting sucked up adequately. And again, you want to work left to right. And you can see there's some minor bleeding associated with this. That tissue then gets all collected in that filter, and you get a pathologic assessment. So this is the pilot study for this. So it was in two centers, and they looked at 19 patients, and these were all colorectal, distal colorectal, like sigmoid and colon fibrotic lesions, probably due to prolapse. Most of the lesions were larger than 2 centimeters in size. They had 84% complete resection rate. Some of the lesions they had to take two sessions to remove, but they had zero perforations. They did have some minor intraprocedural bleeding, and you can see that. They had no major bleeding afterwards, and they had no need for surgery for any of these patients. This is a larger U.S. study looking at this catheter. This was done throughout the GI system, so you could use this in the duodenum or the esophagus. Most of these patients had a history of prior attempts at resection, so these were fibrotic polyps. They had basically a 98% initial successful rate. They had an 80% clinically successful rate. That means that on the follow-up endoscopy, they found about 20% of the patients had residual adenomatous tissue there. The meeting procedure time takes about an hour because you're removing a small area, and you have to basically be patient with it. They do have about a third of the patients have intraprocedural bleeding, 6% delayed bleeding, but they had, again, no perforations for this. This is a technique that I use a lot called hot avulsion. Basically use a hot biopsy forcep. So when I finished my fellowship, we were at the age of taking off diminutive adenomas using a hot biopsy forcep. We stopped doing that because it led to thermal injury. This is different than that. So if you take off a polyp and you have a fibrotic area that you can't get to, that you cannot snare around, you can take a hot biopsy forcep and use the cut setting and basically pull it off the NP layer, and it will quickly come off that area. I find this technique works really well, but you just have to take a lot of time with it because, as you can see, you can't take off a 4-centimeter sequel polyp using this. It's just not practical. But you can take off smaller fibrotic areas, and you can get down to the muscle layer, and I feel like you have good control over what you're doing and you can collect these specimens as you're resecting them. And a pretty clean base. So this is a retrospective review on a single stinner. Basically, they looked at all the polyps that were referred to that stinner for EMR who had a failed previous polypectomy. And so that was a ton of polyps. Some of them lifted well, and the EMR was completed. But what we wanted to focus on was the ones that did not lift, that they had to use this hot avulsion biopsy forcep technique. And you can see that these polyps were located throughout the colon. Most of them had previous EMR attempts. Some of them had a biopsy of the actual lesion itself, which can induce the submucosal fibrosis. And several of them, or some of them, had a spot. The point I wanted to show here was the site of the initial avulsion is pretty small. So it's only 4 millimeters. So you basically will try to resect the polyp like you normally would by raising it up. It's for that little section that is fibrotic that you cannot resect with a snare easily. This is where this technique is working. And I use this a lot, especially in the rectum. They had 100% complete resection rate and a 15% recurrence rate with basically one episode of delayed bleeding and no perforations. This is a larger, more recent study using hot avulsion. It's a retrospective review of basically 112 colon lesions, both on the right and left side. They had postcoagulation syndrome occurring about 2% of the time, and they had a recurrence rate of about 18% as well. One point about a hot biopsy avulsion versus APC. So I finished my fellowship back in 2010, my advanced fellowship. And so at that time, when I would get an EMR and I would find a fibrotic area that I could not resect, I was trained to use APC in that area. But what I quickly found out, that that doesn't work very well, because on the follow-up colonoscopies or the follow-up endoscopy, I'd find that there would be a residual adenoma there. And it would just become a mess. It would become more and more fibrotic, and I'd do more and more APC. And so it was shown then basically in studies like this. This is a large study where they looked at basically 300 lesions referred for endoscopic resection. Several of them they couldn't remove for various reasons, but I'm going to focus on the 223 lesions included in that study. So some of them they can remove just on block, right, and they had a very low recurrence rate. And then they had piecemeal resection as well. But here, these last two arms are the ones that I want you to focus on. So you could do a piecemeal resection of a large colon polyp and then using APC to ablate the residual adenomatous tissue. The recurrence rate was like 60% on follow-up exams versus using avulsion. You can use hot biopsy avulsion or cold avulsion, which basically is using a biopsy forceps to resect that area. I like the hot biopsy forceps because I feel like it leaves a little bit less bleeding when I'm doing it and it's easier for me to see. But the recurrence rate was much less, as you can see. So basically, these techniques, we reviewed three of them, and all of them I find are very safe and effective. Basically, the CAP-assisted is safe, effective. It can be mastered with just minimal increases in your technology that you need to bring to your endoscopy unit. It can be learned with just subtle adjustments in some time. It does potentially lead to mural injury. Those mural injuries are often now treated endoscopically effectively, and that's about a 20% recurrence rate on follow-up exams. Endorotor, again, safe and effective. It is a novel device. Only 50 centers in the United States are using this device. It can lead to some intraprocedural bleeding, and again, also about a 20% recurrence rate. And then hot biopsy avulsion, safe, effective. It's really good for these smaller fibrotic areas, and that's what I use this for. It does take time. You can't do this in, like, your normal colonoscopy half-hour slot or 20-minute slot. You do have to dedicate some time to removing these large polyps. Again, about a 20% recurrence rate. All right, I think that is it. Thank you.

fibrotic lesions

endoscopic procedures

cap-assisted avulsion

endorotor

hot biopsy avulsion