Abdominoperineal resection for squamous cell anal carcinoma: survival and risk factors for recurrence.

Background: Despite the results of combined chemoradiation therapy for anal canal squamous cell carcinoma (SCC), up to 30 % of patients will undergo abdominoperineal resection (APR). The aim of this study was to evaluate oncologic outcomes, survival, and recurrence, following APR for anal canal SCC performed in a single center over a 13-year period.

Methods: All patients who underwent APR for anal canal SCC between 1996 and 2009 were retrospectively included. Demographic data, details on treatments, pathological report, and follow-up were noted. Survival curves were plotted using the Kaplan-Meier method and potential prognostic factors were evaluated using Cox proportional hazards models.

Results: A total of 105 patients (77 women) were included. Indications for APR included tumor persistence (n = 42; 40 %), recurrence (n = 55; 52.4 %), or a contraindication to radiotherapy (n = 8; 7.6 %). Median follow-up was 33.3 months (range, 1.5-174.3 months). Overall survival and disease-free survival were, respectively, 61 and 48 % at 5 years. In multivariate analysis, tumor stage (T3 or T4), positive margin on pathologic examination and existence of distant metastases at the time of the surgery were associated with a poor prognosis. The indication for APR (persistent vs recurrent disease), gender, concurrent HIV infection, or performance of a VRAM flap did not influence OS or DFS. Overall recurrence rate was 42.6 % (n = 43 of 101). The type of recurrence did not exert a significant effect on survival (p = .4571).

Conclusion: This study describes the largest single series of APR for anal carcinoma. Major prognostic factors for survival and recurrence were T status and involved margin. The 5-year overall survival was 60 %.