Long-term survival after treatment for primary anal cancer– results from the Swedish national ANCA cohort study

Abstract

Background Squamous cell carcinoma of the anus is increasing in incidence but remains a rare disease with good 3- and 5-year recurrence free and overall survival rates of 63%–86%. The treatment includes chemoradiotherapy, mainly with 5-fluoruracil (5FU) and mitomycin. The aim of this study was to describe long-term (up to 9 years after treatment) oncological outcome and the types of treatments given, in a Swedish national cohort of patients diagnosed with anal cancer between 2011 and 2013. Method Patients were identified in the Swedish Cancer Registry. Patients still alive were contacted and asked for consent. Clinical data were retrieved from National Patient Register at the Swedish National Board of Health and Welfare and from medical records. Unadjusted and adjusted analyses were performed for overall survival. Results Three hundred and eighty-eight patients were included in the study of which 338 patients (87%) received treatment with a curative intent. Follow up was 85 months (0–113 months) for patients treated with curative intent (information missing in one patient) 7.5 months (0–55) for patients with treated with a palliative intent. Curative treatment varied and consisted of both chemoradiotherapy and radiotherapy (46–64 Gy) alone. 5-FU, mitomycin and cisplatin were the most used chemotherapy agents. Five-year overall survival for patients treated with curative intent was 73%. In an adjusted analysis 5-FU and mitomycin is associated with a lower mortality than 5-FU and cisplatin but the association was weaker (HR 1.61 (95% CI: 0.904; 2.85) than in the unadjusted analysis Conclusions In this national cohort overall five-year survival was 73% for patients treated with curative intent. As reported by others our results indicate that 5-FU and mitomycin C should be the preferred chemotherapy in treatment for cure.