Eight of 46 (17.4%) patients treated in our trial of continuous hepatic artery infusion (CHAI) of fluorodeoxyuridine (FUDR) by Infusaid pump developed biliary strictures. The lesions were clinically, radiographically, and pathologically identical to the idiopathic sclerosing cholangitis frequently seen in association with inflammatory bowel disease. Treatment included immediate cessation of intraarterial FUDR, and surgical or percutaneous drainage of the biliary tree if it was dilated. Two of the eight patients died of the complication. Three patients stabilized after biliary system drainage, and two patients improved on observation only. The pathogenesis of this complication is not understood. This report details the clinical and pathological features of this entity.