COMBINED CHEMORADIATION THERAPY FOR ANAL CANCER - A REPORT OF 56 CASES

Fifty-six consecutive patients with primary epidermoid cancer of the anus were treated with combined chemoradiotherapy (CRT). No patient had been previously treated. There were 44 women and 12 men, with an age range of 25 to 88 years (median, 62 years). Cancer was located at the anal verge in five and at the anal canal in 51 patients. The tumor extended from the canal to adjacent sites in 37 cases. All patients had their tumors histologically assessed: 54 were squamous cell and two were basaloid carcinoma. Twelve patients had T1, 27 had T2, and 17 and T3 primaries, and eight had inguinal metastatic nodes. The protocol treatment consisted of three cycles of 5-fluorouracil (FU) (750 mg/m2/day x 5 days continuous infusion) and mitomycin C (MMC) (15 mg/m2 intravenous (I.V.) bolus on day 1 of each course) given every 6 weeks. Radiotherapy (RT) was started simultaneously: 36 Gy was given in 4 weeks to the anal region with perineum and the lower and middle pelvis, including inguinal and external iliac nodes. After 2 weeks of rest, a boost of 18 Gy was delivered to the anoperineal region in 10 fractions. Because of toxicity, the planned treatment was performed in 50% of patients: 28 patients received less than three cycles of chemotherapy, and seven patients received less than 49 Gy radiation therapy. Toxicities were mild to moderate, and no patients needed hospitalization. A complete response (CR) was observed in 49 patients (87%), eight of whom had metastatic nodes. A partial response (PR) was assessed in five patients (9%) and stable and progressive disease in 2 patients (4%). Objective response (OR) had no evident relationship with extent of primary, presence of metastatic nodes, number of cycles of chemotherapy, and doses of radiotherapy. Of 49 patients who achieved CR, 12 (24%) developed a local recurrence after a median interval of 8 months (range, 2 to 45 months); 11 of them were submitted to surgical rescue and 8 are alive without evidence of disease. Local recurrence was correlated with the main characteristics of patient and tumor and with treatment, but no clear correlation was observed. Actuarial survival rate at 5 years was 81%. Results of present study are compared with those reported by others, and crucial questions concerning combined chemoradiationtherapy are discussed. The authors conclude that chemoradiotherapy is a highly effective treatment of anal cancer, which should be employed as primary approach regardless of different characteristics of patient and tumor.