Y-ECCO Literature Review: Rajan N Patel

In this study, Attar and colleagues evaluate the safety and effectiveness of a dedicated removable anti-migration partially covered self-expandable metal stent for the treatment of Crohn’s Disease strictures in real world practice.

Key Findings

The researchers performed a combined retrospective (n = 39, 84.8%) and prospective (n = 7, 15.2%) nationwide observational study across ten centres of 46 patients with stricturing Crohn’s Disease treated with the uniquely designed anti-migration stent (Hanarostent HRC, MITech, Seoul, South Korea). This novel stent has a longer upstream uncovered collar with a more acute angle to theoretically allow for a degree of embedding into the mucosa.

Stringent inclusion criteria specified obstructive symptoms related to a single stricture and stricture length less than 5 cm. Stents were extracted seven days after deployment via a second colonoscopy. Eighty-seven percent of the cohort had a history of intestinal resection, 74% of strictures were anastomotic and 78% had undergone previous EBD, suggesting inclusion of patients with a more aggressive refractory phenotype.

Stent insertion and removal were technically successful in all cases. Stent migration was seen in only 6.5% of patients (compared with migration rates of around 30% in patients with oesophageal stents and almost 80% in those with fully covered intestinal stents). There may be potential to reduce this even further with use of an over-the-scope clip to fix the stent in place. The atypical upstream direction of migration, probably due to the unique stent design, could be favourable as it may allow for stent salvage by pulling the stent back into the correct position. There were no perforations.

Day 30 clinical success was recorded in 93.5% and therapeutic success after 26 months of median follow-up (defined as absence of obstructive symptoms without the need for new endoscopic or surgical intervention) was 58.7%. A new surgery and new EBD were required in 17.4% and 17.4%, respectively. Of those requiring EBD, only one dilation was required in six out of eight cases (75%), signalling that correctly sited removable stents may reduce the need for repeated dilations and thus also reduce the ensuing cumulative risk of perforation. The median time between stent placement and a new endoscopic dilation was 20.4 months.

Multivariate analyses demonstrated that peri-anal disease at diagnosis (HR 0.1) and cessation of immunosuppression (HR 0.12) were associated with lower likelihood of success. This finding supports the existing knowledge base of approaching patients with poor prognostic features and high inflammatory burden with combination therapy. Performing small bowel MRI before stent placement was linked with significantly higher probability of therapeutic success (HR 5.3) and recognises that comprehensive preparation before intervening can optimise outcomes.

Conclusion

Therapeutic success was seen in almost 60% of patients at an average of more than two years of follow-up, which meant that patients had complete disappearance of obstructive symptoms and no further endoscopic or surgical intervention. 

Ongoing adjunctive treatment with combination immunosuppression, as opposed to monotherapy, would be advisable in those with perianal disease and high inflammatory burden. Paradoxically, limiting immunosuppression and surgical interventions may be contemplated in view of the pandemic, and a temporary stent used in isolation may have a role in bridging patients to combined therapies in the future.

This study is limited by its observational design and small sample size. We await an independent prospective randomised controlled trial to guide patient selection further. Cost-effective analysis in future studies will assist in positioning endoscopic stenting within the existing stricture management paradigm. Since patients were not well balanced across centres, as with most newly introduced medical devices, experience from a few expert endoscopists is advisable prior to more widespread use in order to ensure safety.

This real world cohort study of a novel anti-migration stent for Crohn’s Disease-related strictures demonstrates both safety and effectiveness and offers another therapeutic option for patients with aggressive disease, prior to intestinal resection.

References

1. Shen B, Kochar G, Navaneethan U, et al. Role of interventional inflammatory bowel disease in the era of biologic therapy: a position statement from the Global Interventional IBD Group. Gastrointest Endosc. 2019;89(2):215–37.
2. Veld JV, Fockens P, van Hooft JE. Mistakes in enteral stenting and how to avoid them. UEG Education 2019;19.

Rajan N Patel – Short Biography

Rajan is a consultant gastroenterologist and general physician. He trained in London and is currently working in New Zealand. He has a passion for teaching and innovation.