Endoscopic submucosal dissection for suspected early gastric cancer: absolute versus expanded criteria in a large Western cohort

Background and Aims: Endoscopic submucosal dissection (ESD) is an effective, minimally invasive, surgery-sparing technique for the treatment of early gastric cancer (EGC). It is not well established whether EGC within the Japanese expanded criteria can be safely and effectively treated using ESD in the West. We describe the outcomes of ESD for endoscopically suspected, biopsy specimen-confirmed EGC and its adenomatous precursor lesions (pEGC) using the Vienna classification of dysplasia in a Western cohort. Methods: Prospective data were collected on all pEGCs undergoing ESD at a single expert endoscopy center. Outcomes were compared among pEGC, satisfying the Japanese absolute and expanded criteria, those outside criteria, and those specimens that contained low-grade dysplasia (LGD) only. Specialist GI pathologists reviewed and classified all ESD specimens. Patients were followed up at 6 and 12 months. Results: Over 71 months, 135 pEGCs in 121 patients (mean age, 72.0 years; 61.2% men) underwent ESD. Median pEGC size was 20 mm (interquartile range, 15-30), and 62 (45.9%) satisfied the expanded clinical criteria. Perforation occurred in 1.5% and postprocedural bleeding in 5.2%. Forty-two pEGCs (31.1%) contained LGD only. Rates of en bloc and R0 resection were 94.8% and 86.7%, respectively. One hundred seven pEGCs (79.2%) met the absolute or expanded criteria for endoscopic cure. Two pEGCs recurred during follow-up. Ten of 26 patients with pEGC (38.5%) outside criteria for cure underwent surgery after ESD with residual tumor detected in 3 specimens. Fifteen patients with outside criteria for pEGCs did not undergo surgery because of frailty or their expressed wish. Eleven of 15 patients have so far undergone first surveillance with 1 of 11 experiencing endoscopic and histologic recurrence. Conclusions: ESD is a safe and effective treatment for pEGCs in a Western context. Patients who either decline or are too frail for surgery, with outside criteria resections, may benefit from ESD for local disease control. Large Western studies of ESD for pEGCs are required to define long-term patient outcomes and surveillance guidelines, particularly where pathology shows LGD or high-grade dysplasia only.