Risk of metastatic recurrence after endoscopic resection for esophageal squamous cell carcinoma invading into the muscularis mucosa or submucosa: a multicenter retrospective study

We aimed to elucidate the risk of metastatic recurrence after endoscopic resection (ER) without additional treatment for esophageal squamous cell carcinomas (ESCCs) with tumor invasion into the muscularis mucosa (pT1a-MM) or submucosa (T1b-SM). We retrospectively enrolled patients with pT1a-MM/pT1b-SM ESCC after ER at 21 institutions in Japan between 2006 and 2017. We compared metastatic recurrence between patients with and without additional...