Early post-operative 5-fluorouracil does not affect the healing of experimental intestinal anastomoses

5-Fluorouracil (5-FU) remains the mainstay for systemic treatment of colorectal cancer. In view of the increasing interest in peri-operative administration of antineoplastic agents, we have investigated the effects of early postoperative 5-FU on the healing of intestinal anastomoses in the rat. Animals underwent resection and anastomosis of both ileum and colon and 5-FU (20 mg/kg body weight) was given, either intravenously or intraperitoneally, on the day of surgery and the two subsequent days. Healing was assessed three and seven days after operation. Administration of 5-FU led to a reduced white blood cell count. However, anastomotic strength was not significantly reduced at either time point and anastomotic hydroxyproline content was not significantly affected. We suggest that limited use of 5-FU during or immediately after operation does not necessarily affect early anastomotic healing in the intestine.