Histological complete response in a case of advanced gastric cancer treated by neoadjuvant TS-1 combined with CDDP therapy

A 63-year-old woman with advanced gastric cancer was referred to our hospital.Upper gastrointestinal endoscopy revealed a type 2 tumor in the lesser curvature of the angle of stomach. Moderately-differentiated adenocarcinoma was found in the biopsy specimens. Lymph node metastases of No.3 and No.7 were suspected by abdominal CT. We diagnosed the tumor as cStage III A (cT2N2H0P0M0) gastric cancer.For better curability, we selected neoadjuvant chemotherapy with TS-1/ CDDP. Two courses were completed without serious side effects. Upper gastrointestinal endoscopy and abdominal CT revealed that the primary tumor and metastatic lymph nodes had become smaller, suggesting that a partial response had been achieved. The patient underwent curative surgery, including distal gastrectomy and D2 lymph node dissection.No cancer cells were found by pathological evaluation of the resected stomach and all the regional lymph nodes, confirming a pathological complete response. It is suggested that the neoadjuvant chemotherapy is a useful therapeutic strategy for advanced gastric cancer.