Assessment of tumor extension to the ductal system of submucosal glands in patients with superficial esophageal squamous neoplasms: Implications for endoscopic resection

Background: Endoscopic submucosal dissection (ESD) has become the standard treatment for superficial esophageal squamous cell neoplasia (SESCN); however, local recurrence still occurs occasionally even in patients who meet the current curative criteria. Esophageal ducts of the submucosal gland may serve as a pathway for the spread of SESCN to a deeper layer. However, the clinical impact of ductal involvement (DI) in patients undergoing ESD has yet to be investigated. Methods: We consecutively enrolled patients with SESCN who were treated with ESD. The resected specimens were meticulously reviewed in multiple section slices for the presence and resected margins of DI, and their correlations with clinical factors were evaluated. Results: A total of 210 lesions were analyzed, of which 78 (37.1%) presented with DI. The presence of submucosal invasion, lymphovascular invasion (LVI), and DI were indicators of worse prognosis (P < .05). Deep extended DIs were misdiagnosed as deep submucosal invasive cancer in 4 cases (2%). Of the 185 patients who met the criteria for curative ESD (ie, R0 resection and no deep submucosal invasion or LVI), 11 (5.9%) developed local recurrence/metastasis during a mean follow-up of 55.2 months (range, 6 to 140) months. Compared with patients with without DI, patients with DI had worse recurrence-free survival (P = .008, log-rank test) and a higher local risk of recurrence (12.7% vs 2.5%) after curative ESD (hazard ratio, 4.20; P = .038). Conclusions: A precise histological assessment of DI in SESCN is crucial after ESD, given that DI is common and associated with worse outcome. Whether total removal of esophageal glands/ducts can improve outcome requires future study.