Oncological outcomes of abdominoperineal resection for the treatment of low rectal cancer: A retrospective review of a single UK tertiary centre experience.

Background: The use of abdominoperineal resection (APR) in the management of low rectal cancer has received criticism over high rates of incomplete resection due to tumour involvement at the circumferential resection margin. Extralevator abdominoperineal resection has been advocated as a means of improving complete resection. However, Extralevator abdominoperineal resection can result in increased cost, morbidity and reduced quality of life.This study aims to assess the histological features and long-term outcomes of patients undergoing standard abdominoperineal resection and discusses the potential role of Extralevator abdominoperineal resection in this cohort.

Method: A retrospective review of a prospectively maintained database of rectal cancer patients at a single centre. Patients undergoing standard APR were included from 01/06/2007 to 31/05/2012 to allow a minimum 2-year follow-up. Data was collected on age, gender, co-morbidity, pre-operative stage, neo-adjuvant therapy, histology, recurrence and mortality.

Results: Seventy patients were identified (45 (64%) male, median age 67; (range 36-85)). 12 (17.1%) patients had a positive circumferential resection margin; 4 (6.1%) tumours were located anteriorly, 8 (11%) were located posteriorly or laterally and may potentially have been completely resected with extralevator abdomino-perineal resection, Number-needed to treat = 9. Positive circumferential resection margin was more common in advanced tumours (p < 0.001). Local recurrence was more common with positive circumferential resection margins (16.7% Vs 0%, p = 0.027), with no statistically significant difference in 5-year survival, although there was a tendency towards worse survival in these patients.

Conclusion: Positive circumferential resection margin following APR resulted in significantly increased local recurrence with a trend towards poorer survival outcomes. Extralevator abdomino-perineal resection may have benefited some of these patients with locally advanced tumours and postero-lateral recurrences. However, this has to be balanced against exposing patients to increased risk of adverse events. We would recommend selective use of Extralevator abdominoperineal resection for locally advanced and node-positive tumours although further studies to help refine selection criteria are required with long-term follow-up.