Gastric Schwannoma with Enlargement of the Regional Lymph Nodes Resected Using Laparoscopic Distal Gastrectomy: Report of a Patient.

Preoperative differential diagnosis of gastric submucosal tumors has generally been difficult because they are covered with normal mucosa. However, recent advances in endoscopic ultrasound (EUS)-guided sampling of submucosal gastrointestinal lesions have made it possible to achieve preoperative differential diagnosis of gastric submucosal tumors. A 76-year-old woman was referred to our hospital with a gastric submucosal tumor. The tumor was observed in the antrum of the stomach. It was preoperatively diagnosed as a schwannoma after immunohistochemical evaluation of a biopsy specimen, obtained using endoscopic ultrasound-guided fine needle aspiration. A computed tomography scan of the abdomen revealed lymphadenopathies near the tumor indicating the possibility of lymph node metastasis from the gastric tumor. The patient underwent laparoscopic distal gastrectomy with D1 + lymph node dissection. The resected tumor was a submucosal tumor measuring 65 × 45 × 35 mm; it was histopathologically diagnosed as a schwannoma. Resected lymph nodes were enlarged in the absence of lymph node metastasis as a result of reactive lymphadenopathy. A definitive preoperative diagnosis of gastric schwannoma is possible using immunohistochemical staining techniques and EUS-guided sampling techniques. After definitive preoperative diagnosis of gastric schwannoma, minimal surgery is recommended to achieve R0 resection.