Cancer of the anal canal. Model for preoperative adjuvant combined modality therapy.

An analysis of preoperative multimodality adjuvant therapy with 5-fluorouracil, mitomycin-C, and radiation therapy revealed that 38 of 45 patients (84 percent) treated were rendered free of cancer after chemotherapy/radiation therapy. No recurrence of tumor has been noted in those patients rendered free of disease by the preoperative treatment. Seven patients (15 percent) with residual macroscopic or microscopic cancer after preoperative therapy have had recurrence, all in distant sites. These seven patients have died from the disease. The prognosis for patients in this series depended on the success of the preoperative therapy in eradicating all tumor prior to surgery. Mitomycin-C and 5-fluorouracil are cytotoxic for local disease and for microscopic distant disease as well. Abdomino-perineal resection is unnecessary for patients whose primary tumor is eradicated by the preoperative therapy. The role of the relatively low dose of radiation therapy needs to be further defined.