Aziridinylbenzoquinone (AZQ: NSC-182986), is a quinone derivative which has been shown to have activity in implanted murine tumor systems. Toxicity in small and large animals included hypothermia, diarrhea, anorexia, emesis, weight loss, and gastrointestinal bleeding. In addition, there was myelosuppression and elevated liver function tests. In a phase I study at the Mayo Clinic, dose-limiting toxicity was myelosuppression. Patients with prior radiation therapy or prior chemotherapy were more sensitive to this toxicity. A dose schedule of 27.5 mg/m2 q4 weeks was recommended for patients who had had no previous chemotherapy and 22.5 mg/m2 for previously treated patients or for patients who had had extensive prior radiation therapy. The objective of this study was to determine therapeutic activity for AZQ in patients with advanced colorectal adenocarcinoma.