[Extragastric growth type carcinoma of the stomach with cyst formation].

A 65-year-old man presented with epigastralgia in our department. Contrast-enhanced computed tomography scan showed a large cystic tumor of about 12 cm in diameter attached to the gastric antrum and transverse colon. Gastric endoscopy revealed type 2 advanced gastric cancer located at the greater curvature of the antrum, and the posterior wall of the stomach was pressed from the outside. The result of tumor biopsy was adenocarcinoma. Positron emission tomography -computed tomography showed a markedly increased uptake of fluorodeoxyglucose to the tumor. With a diagnosis of extragastric growth type carcinoma of the stomach with cystic change, a distal gastrectomy, D1+lymph node dissection, and partial resection of the transverse colon was performed. A histological examination of the specimen confirmed tub2- por1, medullary type, INF b, se, ly0, v1, n0 in stage IIb, and no infiltration to the transverse colon. His postoperative course was uneventful 12 months after operation.