We're going to the next presentation, it's our pleasure to invite Carme Lloras. She's acting of her close friends, and she's published some landmark papers recently in the area of endoscopic stenting. She's based at the Hospital Inverster Muta de Teresa in Spain, and we want to talk on the topic of endoscopic stenting, prime time yet. Carme, welcome. Thank you to Dr. Chen and Dr. Nabanizan for inviting me to this conference, and for giving me another time the opportunity to talk about the stenting in IBD. Let me start with a brief introduction. Stenosis is one of the most common complications in patients with Crohn's disease, causing morbidity and the possible repeat surgeries. The primary endoscopic valvulation is endoscopic treatment of choice. Severe non-control observational studies and meta-analysis have shown that endoscopic valvulation is safe and effective, with an overall success rate that ranges from 60% to 80%, with a 4% to 6% percentage of major complications. Then it's critical to find alternative conservative measures to avoid or delay surgery in Crohn's disease patients with stenosis. Both expandable metal stents were initially uncovered and designed for colonic malignancy as palliative treatment without the intention of removing them. The stents can be currently used in mainline disease due to their technological evolution and their effectiveness in malignant stenosis. We have different types of stents regarding their size, material, cover, shape. Taking into account the current evidence and the stents available today, for IBD we have mainly these four types of stents. Fully and partially covered metal stents, lumen-opposing metal stents, or biodegradable stents, being this last one the only stent that can be inserted through the channel, and having these two stents the greater evidence. The partially covered metal stent from Hanaro is 60-80mm long and 20mm wide, and the fully covered metal stent from Taiwan has more sizes, available from 60-150mm long and 18-22mm wide. The information regarding the efficacy and safety of stents in the treatment of structures in IBD patients is limited. Here you can see all the cases and studies published from 1997 until the present. The first reports of stents were case reports that are summarized in this review about the role of stents in the treatment of chronic disease structures. From 1997 until 2010, we have a total of nine studies involving 12 cases and with the placement of 20 stents. It's difficult to draw conclusions regarding the efficacy from these studies, given the wide heterogeneity of patients include the type of stent used, and the fact that in half of the cases the stent placement was a bridge therapy to surgery. There are two recent case reports that deserve a special mention. One of them is rectal colon anastomosis treated with lumen-opposing metal stents, and it's the only case of IBD patients reported with this stent in the literature. In the other case, it's the only ulcerative colitis patients treated with stems for poach inlet structures. Then we find four small series of patients treated with stems, published in 2012. The first series with five patients they use an uncovered metal stent, and in one case the duration of the stenting was nine years, with a clinical success rate of 80%. Then we have the first paper from ATAR with 11 patients. They use a fully covered metal stent, being the stent migration the rule, and with a poor clinical success rate of 36%. For the same group, and though these poor results, they use a partially covered metal stent in seven patients, with a clinical success rate of 71%. Then we have our first study, and until that moment, the largest series of patients treated with stems in IBD. A total of 25 patients were placed in 70 patients. Although we had 13 spontaneous migrations, we achieved a clinical success rate near of 65%, with a mean follow-up of 67 weeks. In 2020 and 2021, two retrospective studies with 21 and 46 patients were reported. And thus, in this year, we have our second study, the first clinical trial, a pro-delayed study with 39 patients. The two retrospective studies that we commented before use this partially covered metal stent from Hanaro, while the clinical trial used the fully covered metal stent from Taiwab. As you can see, the clinical success rate has been very similar within the three studies, around 55-60%. The study by DAS, with 21 patients, most of them anastomotic stenosis, obtained a symptomatic benefit of 81% in per protocol analysis, but with intention to treat analysis of 54%, with a follow-up from three to 50 months. In the other study, with this partially covered metal stent from the French group, at 46 patients, were evaluated, 34 of them anastomotic stenosis, finding a clinical success rate of 58%, with a mean follow-up of 26 months. Then we have our clinical trial to compare the stents versus endoscopic valvodilation from the latter study. A total of 80 patients were analysed, the primary endoscopic treatment was stent placement in 39 patients, and endoscopic valvodilation in 41 patients. The efficacy of the primary endoscopic treatment, defined by the percentage of patients free of a new therapeutic intervention due to symptomatic recurrence at one year of follow-up, was greater for endoscopic valvodilation than for stent placement, with a success rate of 80% versus 51%, in intention to treat analysis, with very similar success rate in per protocol analysis. There were only five complications in 80 patients, that represents a percentage of 6.3, two perforations, one in each group, and three minor complications. Also endoscopic valvodilation had longer symptom-free survival than fully covered metal stents. In a sub-analysis of the success of the endoscopic treatment in accordance with the structure length, the difference between the two treatments disappears when the structure length was more than 3 cm. Finally, a direct cost analysis was carried out, showing that the mean cost of endoscopic valvodilation was cheaper than fully covered metal stents, with a difference of more than 100 euros. After this paper is published, and I know that it will be considered in the reviews about stents in IBD, I decided that I have to mention it, and also I wrote a letter to the editor that has been accepted to publish. This study compares the efficacy of endoscopic valvodilation and STEMs in Crohn's disease structures. It's a study that has a poor methodology that can induce a bad clinical practice based on a theoretical randomized clinical trial of very poor quality. The study has important methodological shortcomings that make it difficult to draw firm conclusions. Apart from the sample size calculations, the problems that they had with that, during the study, the protocol was modified and endoscopic valvodilation was performed prior to STEM placement in 4 of the 7 patients, meaning only 3 patients treated with STEM alone. It's necessary to improve the design of the stents, and this is a prototype that we are working with Taiwan, whose ends are like LAMP stents and could be flanged. Regarding biodegradable stents, to data, only 2 small series of patients with 11 and 6, and 2 key reports were published with poor results. Although STEMs is a safe treatment, there are some adverse events that we have to take into account. The first one is the migration of the stent. This can be proximal and usually happens during STEM placement, and can be endoscopically resolved, but it could be a major complication if endoscopic removal is not possible and surgery is needed. The distal migration usually is not considered an adverse event if it's the consequence of stenosis relief. Nevertheless, this issue has been considered in some papers a complication, as it will imply a lower efficacy of the stent. The adherence of the stent in the mucosal membrane of the bowel. Especially, this happens with partially covered metal stents or fully covered metal stents placed for a long time. The perforation. This can cause by the ends of the stent, and it's usually not reported as a temporary treatment, or caused by a distal migration. In this case, it has been reported that the stent was trapped in a diverticulum located in tortuous stigma. And the last one is the abdominal pain, that usually has been reported with partially covered metal stents, and in some cases, admission and or early removal of the stents could be required. Now I would like you to mention some practical aspects that can help us to perform the procedure and also to avoid some of the above complications. The first one is the study of disease activity and stenosis before STEM placement. This allows us to choose the correct stent. It's mandatory to perform with fluoroscopy. It's helpful to use a long soft guide wire and to pass a catheter or fogarty balloon to inject contrast and to confirm both proper positioning and a better characterization of the stenosis. As you can see here. To avoid migration, we can put clips without tissue adhesive at the distal end of the stent, or insert more portion of the stent inside the stenosis. After placing the stent, it's better not to pass the endoscope as it could dislodge it. It's important to advise a patient a diet with plenty of fluid intake without insoluble fiber. The stent should be left for a period of no more than four weeks for fully covered metal stents or one week for partially covered metal stents. Now I have to switch off my camera for a correct visualization of the video. The first video that I wanted to show you is a stent insertion in ileocecal valve stenosis in chronic disease patients with a fully covered metal stent from Taiwong. First, we pass the guide wire with endoscopic and fluoroscopic control. Then we pass the stent over the guide wire and we begin to open always slowly and with the help of endoscopic and fluoroscopic control. We have to be careful to avoid the proximal migration of the stent. Here you can see the total deployment of the stent. In this case, we put clips to avoid the distant migration. The other video that I wanted to show you is a stent insertion in stenosis of ileocolonic anastomosis in chronic disease patients with partially covered metal stent from Hanaro. The stent placement is equal as above video, but here the interesting part is the stent removal. The interesting part is the stent removal. Well, here we use Fogarty-Ballon that in the other video we didn't use. And now, as you can see, at seven days after the stent placement, the stent was very embedded in the mucosa of the bowel and was very difficult to remove it. At the end, and after some attempts with different tools, an Argonne application, as you can see here, we got it. But it was very, very difficult. Now you will see the stent outside of the patient. And the aspect of the stenosis. Given the current available information, I propose a therapeutic algorithm of endoscope management for structures in chronic disease. In uncomplicated symptomatic stenosis, first to perform balloon dilation. Then we have two options, stent placement or stryptorotomy. In this, with this later option, it will have to be a short stenosis and done by spare endoscopies in this technique. Regarding stents, we have different options according to the type of the stents. Fully covered metal stents for longer stenosis, partially covered metal stents for shorter stenosis, and lamps for shorter and distant stenosis. Then, to conclude, a stent should not be considered the first option in the treatment of stenosis in chronic disease. Endoscopic balloon dilation has a high, has a very high success rate, and it's also cheaper. The stents could work, in those cases, refractory to previous endoscopic treatment with endoscopic balloon dilation. In cases in which endoscopic balloon dilation has not been possible, we induce stenosis of greater length. Stents and not biodegradable stents are the only stents that have shown to play a role in the therapeutic algorithm for stenosis in chronic disease. Finally, regarding the type of the stents, despite the current poor evidence, the best treatment option may be the placement of a fully covered metal stent in longer stenosis or partially covered metal stents in shorter stenosis. Stents are a safe treatment, but some adverse events should be considered. Distal and proximal migration, adherence in the mucosa of the bowel, perforation, and abdominal pain. The future development of this treatment will see the improvement in the design of the stents, especially adapted for IBD or benign stenosis, which improve radial force and avoid early migration of the stent, and all stents-related medication. And remember that to cut is not to cure. This brings me to the end of my presentation. If you have any questions, I will be happy to answer them. Thank you very much for your attention.

endoscopic stenting

Crohn's disease

stenosis

endoscopic valvulation

IBD patients