A 50-year-old man was diagnosed with advanced gastric cancer(Borrmann type 3)accompanied with N3.Staging laparoscopy revealed invasion to the transverse mesocolon and positive cytology from peritoneal washing (CY1). After the patient underwent gastrojejunostomy, we administered DCS combination chemotherapy consisting of docetaxel (40 mg/m² intravenously on day 1), cisplatin(60 mg/m² intravenously on day 1), and S-1 (orally 80 mg/m² on days 1 to 14).Four courses of this treatment were provided every 4 weeks, and it resulted in a partial response (PR).We performed curative distal gastrectomy with transverse mesocolon resection and D2 plus 14v lymph node dissection. Cytological analysis of the samples obtained after peritoneal washing showed negative results.Histopathologically, no variable cancer cells remained in the primary lesion, but a few degenerated cancer cells remained in one of the lymph nodes.Pathological features were classified as Grade 3 for the primary lesion and Grade 2 for the lymph node lesions.S -1 and S-1/cisplatin were administered as adjuvant chemotherapy.One year and 6 months after surgery, the patient is alive and free of disease.