Learning Curve for Endoscopic Submucosal Dissection With an Untutored, Prevalence-Based Approach in the United States.

BACKGROUND & AIMS: Endoscopic submucosal dissection (ESD) is widely used in Asia to resect early-stage gastrointestinal neoplasms, but use of ESD in Western countries is limited. We collected data on the learning curve for ESD at a high-volume referral center in the United States to guide development of training programs in the Americas and Europe. METHODS: We performed a retrospective analysis of consecutive ESDs performed by a single operator at a high-volume referral center in the United States from 2009 through 2017. ESD was performed in 540 lesions: 449 mucosal (10% esophageal, 13% gastric, 5% duodenal, 62% colonic, and 10% rectal) and 91 submucosal. We estimated case volumes required to achieve accepted proficiency benchmarks (>90% for en bloc resection and >80% for histologic margin-negative (R0) resection) and resection speeds >9cm2/hr. RESULTS: Pathology analysis of mucosal lesions identified 95 carcinomas, 346 premalignant lesions, and 8 others; the rate of en bloc resection increased from 76% in block 1 (50 cases) to a plateau of 98% after block 5 (250 cases). The rate of R0 resection improved from 45% in block 1 to >80% after block 5 (250 cases) and ∼95% after block 8 (400 cases). Based on cumulative sum analysis, approximately 170, 150, and 280 ESDs are required to consistently achieve a resection speed >9cm2/hr in esophagus, stomach, and colon, respectively. CONCLUSIONS: In an analysis of ESDs performed at a large referral center in the United States, we found that an untutored, prevalence-based approach allowed operators to achieve all proficiency benchmarks after ∼250 cases. Compared with Asia, ESD requires more time to learn in the West, where the untutored, prevalence-based approach requires resection of challenging lesions, such as colon lesions and previously manipulated lesions, in early stages of training.

A novel technique of endoscopic submucosal dissection for circumferential ileocecal valve adenomas with terminal ileum involvement: the "doughnut resection" (with videos).

BACKGROUND: Ileocecal valve (ICV) lesions are difficult to resect endoscopically and patients are often referred for laparoscopic colectomy. ICV involvement has been shown to be related to technical failure and tumor recurrence after endoscopic mucosal resection (EMR) and represents a challenge for endoscopic submucosal dissection (ESD). Few publications have focused specifically on endoscopic management of ICV lesions. METHODS: We developed a novel ESD technique, the "doughnut resection," for circumferential ICV adenomas with terminal ileum involvement. Two circumferential mucosal incisions are performed, one in the ileum and the other in the cecum, followed by submucosal dissection of the disk of tissue between the two incisions around a guiding stent placed across the valve that helps guide the dissection as it crosses the valve orifice. The lesion is removed en bloc in the shape of a "doughnut" with two concentric assessable lateral margins. The underwater ESD technique and a gastroscope were used to facilitate the resection. RESULTS: Seven patients received the doughnut resection. The median patient age was 67 years. All patients had prior biopsy and three had prior endoscopic resection (1-6 times). The median specimen diameter was 4.5 cm (range 3-8). All resections were en bloc and R0. There was no perforation, delayed bleeding, or other clinically significant adverse events. After a median follow-up of 21 months (range 12-32), there was no tumor recurrence. CONCLUSION: The "doughnut resection" is a feasible, safe, and effective method to remove circumferential ICV lesions endoscopically even for patients with multiple prior tumor manipulations.