Clinical and oncological outcomes of pelvic exenteration surgery for anal squamous cell carcinoma

Aim: Anal cancer incidence and mortality rates are rising in the United Kingdom (UK). Surgery is an important treatment modality for persistent or recurrent disease. There is a paucity of data on outcomes for patients undergoing pelvic exenteration for anal squamous cell carcinoma (SCC) for persistent or recurrent disease. The aim of this study was to investigate the outcomes for patients who were treated with pelvic exenteration for anal SCC from two high-volume, high-complexity pelvic exenteration units in the UK.Method: A retrospective review of prospectively maintained databases from 2011 to 2020 was undertaken. Primary endpoints included R0 resection rates, overall and disease-free survival at 2 and 5 years.Results: From 2011 to 2020, 35 patients with anal SCC were selected for exenteration. An R0 resection was achieved in 26 patients (77%). Of the remaining patients, seven patients had an R1 resection and one had a R2 resection. One further patient was excluded from additional analysis as the disease was inoperable at the time of laparotomy. With a median follow-up of 19.5 months (interquartile range 7.9-53.5 months), overall survival was 50% (17/34). Patients with an R1/2 resection had a significantly poorer overall survival [0.27 (0.09-0.76), p = 0.021] than those patients in whom R0 resection was achieved. Disease-free survival was 38.2% (13/34) and an R1/R2 resection was associated with a significantly reduced disease-free survival [0.12 (0.04-0.36), p < 0.001].Conclusion: Complete R0 resection for recurrent or persistent anal SCC is possible in the majority of patients and improves overall and disease-free survival compared with R1/R2 resection.