A case of gastric granular cell tumor successfully treated by laparoscopic and endoscopic cooperative surgery.

We describe a case of gastric granular cell tumor (GCT) treated with laparoscopic and endoscopic cooperative surgery (LECS). A 30-year-old male was referred to our hospital for the investigation of a subepithelial lesion (SEL). Contrast-enhanced computed tomography and esophagogastroduodenoscopy revealed a 15 mm SEL within the posterior wall of the gastric body. Endoscopic ultrasound revealed a well-demarcated, homogenous, hypoechoic lesion in the submucosa, suggesting partial invasion into the muscularis propria. Biopsy using the bite-on-bite technique showed a gastric GCT diagnosis. The patient underwent LECS, and pathological findings confirmed a benign gastric GCT without muscularis propria invasion, lymphovascular invasion, or lymph node metastasis. The patient remained recurrence-free after 24 months.Despite unresolved issues such as setting the resection margins; indications for resection, and accurate preoperative diagnosis of the invasion depth, including muscularis propria invasion, LECS may be useful for gastric GCT in the form of SEL, especially for lesions that cannot be ruled out to invade the muscularis propria invasion.