Y. Alamri, P. Buchwald, L. Dixon, B. Dobbs, T. Eglinton, J. McCormick, C. Wakeman, F.A. Frizelle

Anal squamous cell cancers are uncommon, and primary treatment is radical chemoradiotherapy. The role of radical surgery is in salvage of patients with residual and recurrent disease. The primary aim of the study is to determine how often such salvage surgery is required, while the secondary aim is to determine which features indicate salvage surgery may be required and to determine the outcome of salvage surgery. A prospective database was analysed of all patients with anal cancer over an 18 year period (Dec 1996-Jan 2015). The records of patients requiring salvage surgery were reviewed. 203 Patients were identified with anal cancers, of which 180 had squamous cell anal carcinoma. 112 Female (median age 59.4, range 33-92) 68 male (median age 63.8 range 36-87). Of these 27 patients (15%) required salvage surgery. 23 Patients had a R0 resection. 18 Patients had an extended resection (16 R0) while 9 had a routine APR (7 R0). The 30-day post-operative mortality rate was 0%. The overall 5 year survival was 78%, not significantly different from those not requiring salvage surgery (p = 0.23). Age, gender, AJCC stage, T stage, radiation therapy alone, were not predicators of the need for salvage surgery. Salvage surgery is uncommonly required. Extended surgery beyond routine APR is often required to obtain an R0 resection. Excellent patient survival can be achieved in highly selected cases. There were no identifiable clinical predictors of those needing salvage surgery, and consideration should be given to explore molecular and genetic factors.