Two cases of stage IV gastric cancer treated by resection of the primary tumor after chemotherapy combined with trastuzumab

: We report 2 cases of stage IV gastric cancer in which the primary tumor was resected after chemotherapy combined with trastuzumab was administered. Case 1: A 57-year-old man who reported epigastric discomfort was diagnosed as having gastric cancer with Virchow's lymph node metastasis. Because his gastric cancer was human epidermal growth factor receptor( HER)-2-positive, he was treated with trastuzumab+capecitabine and CDDP( XP therapy). After 2 courses of this treatment, he underwent distal gastrectomy because of advanced pyloric stenosis. He was treated postoperatively with capecitabine+trastuzumab, and the residual lymph node shrank. Case 2: A 62-year-old man examined for weight loss was diagnosed as having gastric cancer with peritoneal metastases. Because his gastric cancer was HER2-positive, he was treated with trastuzumab+S-1 and CDDP( SP therapy). After 5 courses of this treatment, he underwent total gastrectomy because of advanced pyloric stenosis. He was treated postoperatively with trastuzumab+SP therapy, and his condition remained stable. Chemotherapy combined with trastuzumab could allow resection of the primary tumor and thereby improve the prognosis.