OBJECTIVE This study was designed to assess results of chemoradiation therapy for epidermoid carcinoma of the anal canal. METHODS A retrospective review of records of the prospective database revealed 35 patients who had been diagnosed with anal canal carcinoma and treated with chemoradiotherapy at Wilford Hall USAF Medical Center (tertiary referral hospital) from 1981 to 1991. RESULTS Patients ranged in age from 35 to 80 (mean, 59) years, and 63 percent were women. Primary tumors ranged from 1 to 8 cm in diameter (mean, 3 cm). The first six patients had an abdominoperineal resection (APR) after chemoradiotherapy, and no residual tumor was identified in the specimens. In the subsequent 29 patients who did not have APR, 5 had moderate problems with anal continence, and one required a diverting colostomy for incontinence. Follow-up ranged from 4 months to 12.9 years (mean, 5.2 years). There were two pelvic recurrences, and three patients developed distal metastasis. Eight patients died during follow-up, including three with recurrent or persistent disease. Five-year survival using life-table analysis was 89 percent. CONCLUSIONS Long-term follow-up confirms that chemoradiation remains the preferred therapy for epidermoid carcinoma of the anal canal.