A Case of Surgical Resection with a Preoperative Diagnosis of Metachronous and Isolated Sigmoid Colon Metastasis from Gastric Cancer

Abstract

A 57-year-old woman, who underwent total gastrectomy (D2) for Stage IIIC gastric cancer 4 years ago, was referred to our hospital due to the presence of fecal occult blood. Colonoscopy showed a stenotic lesion at the sigmoid colon. Pathological examination of the biopsy specimen showed poorly differentiated adenocarcinoma. The histological findings were similar to those of the gastric cancer of the previous surgery, suggesting metastasis of gastric cancer. No distant metastases and peritoneal dissemination were detected preoperatively. Sigmoidectomy (D3) was then performed. The histopathological findings of the resected specimen were also similar to those of gastric cancer. In addition, immunohistochemical staining showed CK7(+), MUC5AC(+), MUC6(+), MUC2(-), CK20(-), and CDX2(-). Therefore, the present lesion was diagnosed as sigmoid colon metastasis from gastric cancer.