['Submucosal myogenic tumors, including leiomyoma and stromal tumors, are currently treated primarily by open surgery or laparoscopic excision. The aim of this retrospective study was to evaluate the feasibility of endoscopic dissection (ED) for resecting endogenous esophageal leiomyoma (EL) and gastric stromal tumors (GSTs) with diameters of 5 cm.', 'We enrolled 42 patients with endogenous EL and GST who had undergone endoscopic surgery (endoscopic group). These cases were compared retrospectively with 22 patients who had undergone thoracotomy or laparotomy (control group). Endoscopic group (n = 42) received ED for EL and GST resection, including circumferential removal of superficial mucosa of targeted tumor. Control group (n = 22) received thoracotomy or laparotomy for resection of esophageal and gastric myogenic tumors. Main outcome measures were operative time, intraoperative bleeding and perforation, postoperative complications, and hospital stays and costs were compared between groups.', 'Endogenous EL and GST were successfully removed from all patients. Bleeding and perforation occurred in seven and five EL and GST patients, respectively. Bleeding was corrected with argon plasma coagulation (APC). Perforation was endoscopically repaired with clips. Mean operative time was 49 min for endoscopic EL and 55 min for GST resection. No major bleeding or perforation occurred postoperatively. Endoscopic treatment had shorter length of stay and lower hospital costs than conventional procedures.'] Is endoscopic dissection of large endogenous myogenic tumors in the esophagus and stomach safe and feasible : a report of 42 cases?