[A case report of primary adenocarcinoma of the small intestine with peritoneal dissemination treated with multidisciplinary therapy].

A 55-year-old woman consulted our hospital complaining of abdominal distention and vomiting. She was diagnosed with a malignant tumor in the small intestine and an ovarian tumor with an upper gastro-intestinal series based on a computerized tomography(CT)examination. Intra-operative findings showed that the primary tumor was located in the proximal jejunum, 10 cm on the anal side from Treitz's ligament. There were no liver metastases, but the tumor had spread into the peritoneal cavity(light ovary). The jejunum and light ovary were therefore resected. Pathological diagnosis of the resected specimen revealed adenocarcinoma with lymph node metastases(T4N1M1, UICC StageIV). The patient received systemic chemotherapy with oral S-1. A recurrent lesion on the right ovary was detected 6 months after surgery. The patient subsequently underwent resection of the right ovary. For lung metastases and recurrent peritoneal dissemination, combination chemotherapy with XELOX or FOLFIRI, along with capecitabine plus bevacizumab, and cetuximab, was administered. The patient died 33 months after the first surgery. Primary small intestinal adenocarcinoma is a rare disease, and it is often diagnosed at an advanced stage because there are very few characteristic symptoms. This case may be an important case for the development of a standard chemotherapy regimen for advanced and recurrent adenocarcinoma of the small intestine.