5-Fluorouracil-Based Chemotherapy for Unresectable Small Bowel Adenocarcinoma: A Case Report

A 74-year-old female was admitted because of nausea and vomiting due to obstraction of the proximal jejunum. She was diagnosed as having a malignant tumor in the small bowel with an upper gastro-intestinal series and a computerized tomography (CT) examination. Intra-operative findings showed that the primary tumor located in the proximal jejunum 2cm to the anal side from Treitz. s ligament, was 8cm in size, had invaded the transverse colon, transverse mesocolon, and stomach, had had no liver metastasis, but had spread into the peritoneal cavity (T4NxM1, AJCC Stage IV). Pathological examination of the peritoneal seeding samples confirmed this lesion as a tubular adenocarcinoma. A bypass operation with gastro-jejunostomy and transversesigmoid colostomy was performed. She received palliative chemotherapy with 2 courses of low-dose 5-fluorouracil and cisplatin (low-dose FP) treatment followed by oral TS-1 therapy. A partial response in the primary tumor was acquired after the first course of low-dose FP treatment and maintained with TS-1 therapy, as assessed by CT examination. The progression-free survival was 25 months. Adverse effects for low-dose FP treatment were grade 3 stomatitis, dermatitis, nausea, vomiting, and anorexia and grade 2 neutropenia, but for TS-1 therapy were no adverse effects except for grade 1 neutropenia and pigmentation, indicating a good quality of life. This case may be important for developing a standard chemotherapy against advanced and recurrent adenocarcinoma of the small bowel.