Short course preoperative radiotherapy is the single most important risk factor for perineal wound complications after abdominoperineal excision of the rectum

Abstract

Aim: To determine factors associated with perineal wound complications following abdominoperineal excision of the rectum (APER) for rectal adenocarcinoma and their effects on time to healing.

Patients and methods: We studied all cases of APER performed in our unit by four consultants over 7 years. Seven out of nine factors considered important in wound healing were analysed using logistic regression and a multivariate model was built to examine interactions. Wound persistence was calculated using the Kaplan-Meier method.

Results: Data were available for 94 of 96 patients [male:female, 3:2, median age 72.5 (IQR: 64-78)]. Thirty-nine (41%) patients had 25 Gray, 3-portal, fractionated 5-day short course preoperative radiotherapy (SCPRT). Dukes stages were A (34%), B (26%), C (40%). Perineal wound complications occurred in 44 (47%), 16% of these requiring return to theatre. Local recurrences occurred in 13 (15%). There was no evidence to suggest that either patient gender, age, smoking status, preoperative albumin or haemoglobin level, or T stage were associated with the development of wound complications. The odds of wound complications for a patient who had SCPRT was over 10 times that for a patient who did not have preoperative radiotherapy (odds ratio 10.15, 95% CI: 3.80-27.05, n = 94). Seventy-four per cent of SCPRT and 96% of non-SCPRT wounds had healed by 1 year. Estimated failed wound healing rates at 30 and 90 days were 64% (95% CI: 46-78) and 48% (95% CI: 30-64) in SCPRT patients compared with 23% (95% CI: 12-35) and 9% (95% CI: 3-20) in non-SCPRT patients (log rank test P < 0.0001).

Conclusion: Patients who have an APER are over 10 times more likely to have a perineal wound complication if they have SCPRT than not. Two-thirds of these will not have healed by 1 month, half by 3 months and over a quarter will still remain unhealed at 1 year. This has important implications for patient management decisions. Large prospective studies are needed to evaluate the effects of a selective policy for radiotherapy administered to patients requiring APER.