P-20 Concurrent chemo-radiotherapy in anal squamous cell carcinomas: A 10-year retrospective review of a tertiary centre experience

Abstract

Anal cancer is an uncommon form of gastrointestinal malignancy and treatment is often confined to specialist centres. It has a high cure rate with a non-surgical approach resulting in organ preservation. Chemo-radiotherapy (CCRT) remains the standard treatment for these cancers. The current accepted schedule is CCRT with 5FU mitomycin C (5FUMC) and radiotherapy doses between 50.4-53.2 Gray in 28 fractions. This study included patients who had histological confirmation of squamous cell carcinoma and had completed the full CCRT course in our centre for anal cancer between 2008 and 2017. The concurrent chemotherapy was mitomycin C with either 5FU or capecitabine. Some patients received neoadjuvant chemotherapy and some had adjuvant chemotherapy. Data was collected retrospectively assessing basic demographics, staging, surgery, relapse, latest follow-up, and date of death, as well as CCRT regimen. All TNM stages were included and original staging was revised on review of imaging based on TNM 8th edition. Outcome data and stoma reversal rate were analysed. Overall, 87 patients were included in the study. The median age of patients was 60 years. At diagnosis, 94.3% of patients had T2-T4 disease and 44.8% had involvement of positive loco-regional lymph nodes. Overall survival (OS) probability at 1, 3, and 5 years were 98.8%, 87.4%, and 83.7%, respectively. Results also revealed a statistically significant effect of time from diagnosis to radiotherapy start on OS (p=0.039). Sixty-nine (79.3%) patients achieved complete remission at last follow-up. Three (3.4%) patients had a local relapse and 9 (10.3%) relapsed systemically. Six patients (6.9%) had persistent disease. The mean time to relapse was 16 months, and Median OS was 52.3 months. Twenty-one patients (24%) underwent surgery for a defunctioning stoma, only five of these patients subsequently received stoma reversal. Our data reflects the efficacy of CCRT as the primary modality of treatment in the management of anal squamous cell carcinoma with effective organ preservation and disease control. Further studies with increased dose to primary may improve outcomes even further. Early stoma reversal would also improve quality of life.