[A case report of primary adenocarcinoma of small intestine]

This is an account of a case of primary adenocarcinoma of the small intestine with peritoneal dissemination successfully treated with chemotherapy. A 64-year-old woman was admitted with a complaint of severe abdominal distension. Abdominal computerized tomography revealed a bowel obstruction with tumor and the remarkable small bowel dilation of oral side of tumor. The tumor was found at surgery to be at the ileum 15 cm proximal from the ileocecal region. Peritoneal dissemination was recognized around the ileocecal region, so ileum partial resection was performed for the primary cancer lesion and dissemination region. Pathological diagnosis of the resected specimen was adenocarcinoma with lymph nodes metastasis. The peritoneal dissemination consisted of metastatic adenocarcinoma from small intestine. After an operation, internal use of S-1 was performed as adjuvant chemotherapy. But a recurrent lesion at the ovarium was detected 6 months after surgery. The patient was subsequently treated with resection of the ovarium. For lung metastasis, the combination chemotherapy with mFOLFOX6 + bevacizumab was administered. Primary small intestinal adenocarcinoma is a rare disease, and it is often diagnosed as advanced cancer because of few characteristic symptoms. So carcinoma of the small intestine usually has a poor prognosis.