Patterns of recurrence in anal canal carcinoma

HYPOTHESIS: The initial modality of treatment of anal canal carcinoma (ACC) influences the pattern of recurrence of disease. DESIGN: A retrospective analysis comparing patterns of recurrence in patients with ACC undergoing either surgery or chemoradiotherapy as their initial therapeutic intervention. Anal margin cancers and adenocarcinomas were excluded. SETTING: A university-affiliated urban medical center. PATIENTS: Eighty-one patients were given a diagnosis of ACC between February 1, 1952, and December 31, 1998. Fifty-one (63%) of the patients initially underwent surgery: abdominoperineal resection in 38 patients (75%) and local excision in 13 patients (25%). Chemoradiotherapy was the initial therapeutic intervention in 30 patients (37%). MAIN OUTCOME MEASURES: The patterns of recurrence (local vs distant disease) and survival were compared between the group that underwent palliative surgery (hereafter referred to as the surgical group) and the group that received chemoradiotherapy (hereafter referred to as the chemoradiotherapy group). RESULTS: The mean follow-up was 40 months. Local recurrence occurred in 7 patients (14%) in the surgical group vs 7 patients (23%) in the chemoradiotherapy group (P =.46). Using Kaplan-Meier actuarial analysis, local recurrence rates for the surgical and chemoradiotherapy groups at 1 year were 0% and 6%, respectively (P =.32), and at 5 years were 17% and 36%, respectively (P =.02). The average (+/-SD) time to local recurrence in the surgical group was 23 +/- 0.7 months and for the chemoradiotherapy group 16 +/- 2.9 months (P =.27). Five (71%) of the 7 patients with local recurrences in the chemoradiotherapy group underwent salvage abdominoperineal resection with 100% disease-free survival at a mean follow-up of 35 months. When patients presenting with metastatic disease were excluded, distant recurrences developed in 7 patients (16%) in the surgical group and 2 (7%) in the chemoradiotherapy group (P =.31). Actuarial 5-year distant recurrence rates for the surgical and chemoradiotherapy groups were 26% and 19%, respectively (P =.65). Five-year survival was 42% in the surgical group and 74% in the chemoradiotherapy group (P =.01). CONCLUSION: There was a higher rate of local recurrence in patients with ACC treated with chemoradiotherapy vs surgical resection as the initial therapeutic intervention. However, when this occurred, abdominoperineal resection was effective salvage therapy and was associated with a 100% disease-free survival at 3 years. Therefore, chemoradiotherapy is justified as the initial treatment for ACC and has an overall 5-year survival that is significantly higher than that attained with initial surgical treatment.