Radiation dose associated with local control in advanced anal cancer: Retrospective analysis of 129 patients

Background and purposeTo retrospectively analyse a large consecutive cohort of patients with anal cancer for treatment-related factors influencing local control and survival.Materials and methodsAll patients referred for primary radiotherapy at Medical University of Vienna in 1990–2002 with anal canal carcinoma without distant metastases were analysed. Treatment consisted of external radiotherapy with or without brachytherapy and with or without chemotherapy. Patient-, tumour-, and treatment-factors were tested for influence on survival and local control using Cox multivariate analysis.ResultsMedian age was 67 years (n = 129), the UICC stage distribution was 15%, 58%, and 27% for stages I, II, and III, respectively. With median follow-up of 8.0 years for surviving patients (3.9 years including deceased patients), five-year overall survival and disease-free-survival were 57% and 51%, respectively. Local control at 5 years was 87%. Stage and age were significant factors for overall and colostomy-free-survival, N-stage for disease-free-survival. Shorter overall treatment time favoured local control in stage T1–2 (p = .015), higher total radiation dose and female gender were associated with improved local control in T3–4 tumours (p = .021).ConclusionsThese results support potential improvement of anal cancer treatment by studying advanced technology such as IMRT, making it possible to tailor high-dose regions.