TWO CASES OF GASTRIC SMALL CELL CARCINOMA RESPONDING TO POSTOPERATIVE CHEMOTHERAPY WITH MODIFIED EAP REGIMEN

Abstract

We successfully treated two cases of gastric small cell carcinoma that is rare with postoperative modified EAP regimen. A 70-year-old woman with Borrmann 3 type gastric cancer with multiple liver metastases underwent a distal gastrectomy and a lateral hepatic segmentectomy. The histological findings showed diffuse proliferation of small cells with little cytoplasm forming a pseudo-rosette structure and trabecular disportion. The final diagnosis of small cell carcinoma with partial differentiation to adenocarcinoma was made. Atypical small cells were positive for immunohistochemical stains of NSE and chromogranin-A, and negative for CEA. Modified EAP therapy was conducted, and consequently the liver metastases disappeared. There has been no evidence of recurrence as of 23 months after the operation. Another 71-year-old man with Borrmann 3 type gastic cancer underwent a distal gastrectomy. The histological and immunohistochemical findings were much the same as the former's. Modified EAP therapy was conducted, and the para-aortic lymph node metastases disappeared for a time, but he died of peritonitis carcinomatosa 16 months after the operation. These tumors presented here might derive from pluripotential primitive cells that can differentiate into both neuroendocrine and epithelial cells. It is said that the small cell carcinoma of the stomach has a poor prognosis, but we consider that the carcinoma often responds to chemotherapy.