All right, well, thanks to the course organizers, ASG, for the opportunity to be here. Let's see. All right. Exclosures. So I have two cases here, which I'll go through fairly quickly. So this is an indeterminate biliary stricture that was sent to me, a 71-year-old woman, breast cancer with mets to the bone, epigastric pain, mild elevation, and LFTs, and what was described as a cholestatic pattern and had an MRCP externally, showing a stricture in the common hepatic duct down to the mid-common duct. She'd had multiple procedures on the outside, including an EOS that showed ductal thickening in the area of the stricture with a prior non-diagnostic FNA, and several ERCPs with serial stenting, including at least two non-diagnostic brushings and non-diagnostic cholangioscopy biopsies. And so she was sent to us for a diagnosis. So we did a repeat ERCP. You can see the stricture there. Again, this had been stented now for about a year, so she'd been having this. So rather smooth in the distal duct and the common hepatic duct here. And we ended up doing cholangioscopy. And again, when I looked at this, again, these are changes that I attributed. This is a mild erythema, but generally pretty unremarkable here, and I thought these were probably stent-induced changes. And we took multiple biopsies at the time with the sort of expanded, the new enlarged capacity forceps. And I actually told this patient, I said, well, this actually, my visual suggests that this doesn't look too bad. But interestingly, this is one of the times, and that's probably why I presented this case, is where the pathologic accuracy exceeded the visual accuracy. So this actually turned out to be, within the stroma, suspicious for adenocarcinoma. In fact, they ran ERPR, mammoglobulin, and GATA3. And this turned out actually to be an interesting case of an intramural bile duct met of a breast cancer. So it was a malignancy, but obviously was treated differently than what we would traditionally do. So I brought this case up only because it highlights an unusual instance, obviously, of breast cancer going to this location. It also shows the clinical utility of our improved diagnostic tools and biopsies for biopsying indeterminate strictures, allowing for deeper wall sampling, and the potential for immunostaining. And obviously, that had a huge change in management, in terms of both making a diagnosis of cancer, but also the type of therapy that was given to that cancer, which is not traditionally what we would do. So just briefly, before I move to the next case, again, there's a variety of visual criteria that have been developed. Obviously, tumor vessels and polyploid mass are probably the two that are most commonly utilized. Again, you may see some infiltrated, ulcerated lesions. If you see stenosis and you can't entirely get through a biopsy at the margin of the stricture, these are some of the sort of findings that you might see in a malignancy, a luminal narrowing, exophytic tissue, and you see these enlarged vessels that may be there. Here's some pictures of tumor in contrast to what typically is a benign stricture or cholangioscopic findings. Again, Peter and his group looked at this issue in terms of looking at the yield of cholangioscopically directed biopsies as being superior to brushings or just standard forceps biopsies. And then this is a systematic review that shows that the visual accuracy is about 10 points higher usually than the biopsy accuracy, which again is that, you know, we always talk about tissue being the issue, but when it comes to these sorts of cases, really, if you have a clinical suspicion visually, I would recommend that you follow that. So typically, four to six biopsies these days should be sufficient. You can sometimes take multiple biopsies, suction the trap, target nodular areas at the margins in areas with less ulceration. The yield can be improved from some data with on-site evaluation as well of the specimen. If you don't get a diagnosis, but you still are clinically suspicious, I would consider a repeat procedure, additional sampling, possible fluorescence in situ hybridization, and improved optics and visualization and larger capacity forceps are hopefully gonna improve our diagnostic yield and reduce the number of these indeterminate strictures. And there's also now AI algorithms in development to help better identify target areas for dysplasia and cancer. So with that, I'll just quickly move to my second case. This is actually courtesy of my partner because I was looking for a case that included both RFA and a stenting of a cholangio. So here's a patient with basically a large, let me go back to that here just a second. So this patient has a large cholangiocarcinoma that's involving most of sort of the right lobe, and you can see the hypertrophy of the left lobe here, and this is a patient you'll see in a moment that has a very large dilated system there in the left, and again sort of highlights the importance of sort of pre-procedure mapping. In the interest of time, I'm just gonna move through this. So did a pre-cat access to get into the bile duct, but again, no opacification of the duct of interest here. So subsequently moved to an EUS approach, and again, instead of going through IR, we can now essentially do EUS rendezvous. So essentially now through the stomach, we put a wire through actually exchange for an upper endoscope here to sort of get better pushability here and eventually get a wire across the stricture, and then can sort of grab that wire or in some cases put a second wire across, dilate that stricture, place overlapping metal stents across this, and again, unilateral is probably sufficient in this case because the right side is primarily involved by tumor, and this actually goes to show 20 months later, which you wouldn't expect me to say, given that initial image, this patient represented again with obstruction, and then subsequently then the question is how to sort of manage that sort of re-engrowth and both of tissue hyperplasia as well as perhaps tumor, which is definitely the case here. So initially you get a cholangiogram. You can see there's pretty significant stenosis here as you kind of enter up into the left, and then subsequently we do a cholangioscopy here which will sort of nicely demonstrate again that you really see complete overgrowth of the stent here, stenosis here, pushing through this area, and in the past, you know, there's been a couple of techniques that have been utilized for this. Photodynamic therapy has been used in the past and actually has some good data, but it's extremely expensive, leads to photosensitivity as well, and so biliary RFA is an option here, which is what's done. It's actually about a 2.5 centimeter zone of necrosis that you can get, and you can do overlapping treatments. Use seven watts typically within the liver, 10 outside of the liver, usually 90 second treatments, and this can be a very effective way of sort of doing treatments. After the treatment here, balloons used to sort of sweep out some of the debris, and this is the immediate post image, and then subsequently you can either re-stent with plastic or additional metal as needed, and then you can also repeat treatment as necessary for this. So this is a potential alternate way of sort of maintaining stent patency. So I'll just kind of just, I think most folks are pretty familiar with this bismuth classification of strictures. We don't see, unfortunately, too many ones. These are sort of below, two go to the hilum, three up the right, three A up the right, B up the left, and four up both, and tend to see more threes and fours. In general, again, in the ones, typically one stent's needed. I usually do two for bismuth two. Occasionally you can get one, but it depends on how high up it goes. Three A, depending on if it's basically blocking the right anterior and posterior separately or if it's distal to it. If it's distal, you can do two, but if it's up higher, you usually need three, and again, the right side really depends on whether you need two or three. Some general rules on stenting. Again, it's important to get high-quality imaging prior to endoscopic interventions. Talk with your surgeons about what surgery is planned and what's the need for preoperative drainage. Just realize these patients long-term may ultimately need percutaneous drainage. You endoscopically don't necessarily need to drain an atrophic lobe like we did. In fact, that patient actually essentially normalized her bilirubin even though we just did the left. And again, the goal is to drain at least 50% of the non-atrophic liver volume. Obviously, you must need to drain any obstructed segment that's injected, so be cautious in how you do that. You can do, if you do metal stents, stent and stent, or stent within a stent, stent by stent approach, I prefer the latter, and then RFA and PDT can be used to ablate lesions. And there's a nice summary ASG guideline which basically summarizes these recommendations that just came out last year. So I'll stop with that, and thanks for your time.

indeterminate biliary strictures

breast cancer

ERCP

cholangioscopy

diagnostic tools