Split course concomitant radiochemotherapy followed by brachytherapy boost in the exclusive treatment of the anal canal cancer

From 1988 to 1996, twenty-six patients with epidermoid anal cancer were examined at the Radiotherapy Department of Università Cattolica del S.Cuore, Rome. At diagnosis, 13 patients were stage II, 11 patients were stage III, 2 patients had a small recurrence after local excision. All the patients were treated with concomitant radiochemotherapy followed by a brachytherapy boost Treatment was carried out in two cycles 4-5 weeks apart. Chemotherapy consisted of 5FU (1,000 mg/sqm, continuous infusion over the first 4 days) and Mitomycin C (10 mg/sqm on day 1, bolus administration). Radiotherapy was administered with two AP opposed coaxial beams of the same size. The target was T and inguinal, external, internal and common iliac lymph nodes. The total dose for each cycle was 23.4 Gy, administered with conventional fractionation and a daily dose of 180 cGy. Four-six weeks after the end of cycle 2, the patients received a boost of interstitial brachytherapy. During concomitant radiochemotherapy, grade 3-4 (RTOG-EORTC scale) acute hematologic and cutaneous toxicities were observed in 15% and 4% of patients, respectively; treatment was discontinued in 4 patients. Complete response was observed in 21 patients (81%) and partial response in 5 (19%). The latter underwent surgery, namely local excision in 1 patient and abdominoperineal resection in 4 patients. The median observation period of our study population was 45 months. Five-year actuarial local control of the 26 patients was 88%. Five year actuarial survival was 75% and sphincter conservation 77%. Our results confirm the data reported by Cummings of Princess Margaret Hospital, who observed low toxicity when the two cycles of concomitant radiochemotherapy are split. Randomized phase-III studies should clarify the potential role of the new radiochemotherapy combinations which should be compared with reference treatments providing repeatable results and low toxicity. Our treatment may make a reference for more innovative combinations of radiochemotherapy.