Chemoradiotherapy in squamous cell carcinoma of the anal canal

Purpose: We reviewed the treatment outcomes and prognostic factors for patients with anal canal carcinoma who were treated with curative intent chemoradiotherapy (CRT) at Severance Hospital from 2005 to 2011. Materials and Methods: Data for 38 eligible patients treated during this period were reviewed. All patients were treated with curative intent using radiotherapy (RT) with (n = 35) or without concomitant chemotherapy (n = 3). Among 35 patients who received CRT, most of the chemotherapeutic regimens were either 5-fluorouracil (5-FU) plus mitomycin C (23 patients) or 5-FU plus cisplatin (10 patients). Recurrence-free survival (RFS), colostomy-free survival (CFS), overall survival (OS), and locoregional control (LRC) rates were calculated using the Kaplan-Meier method and survival between subgroups were compared using the log-rank test. Cox’s proportional hazard model was used for multivariate analysis. Results: Over a median follow-up period of 44 months (range, 11 to 96 months), 3-year RFS, CFS, OS, and LRC were 80%, 79%, 85%, and 92%, respectively. In multivariate analysis, tumor size >4 cm was an independent predicting factor for poorer RFS (hazard ratio [HR], 6.35; 95% confidence interval [CI], 1.42 to 28.5; p = 0.006) and CFS (HR, 6.25; 95% CI, 1.39-28.0; p = 0.017), while the presence of external iliac lymph node metastasis was an independent prognosticator for poorer OS (HR, 9.32; 95% CI, 1.24 to 70.3; p = 0.030). No treatment-related colostomies or deaths occurred during or after treatment. Conclusion: Curative intent CRT resulted in excellent outcomes that were comparable to outcomes in previous randomized trials. No severe treatment-related toxicities were observed.