Clinical management of 52 consecutive retro-rectal tumours treated at a tertiary referral centre

The aim of this single-institution study was to analyse the diagnostic methods, preoperative work-up and outcomes of 52 retro-rectal tumours.

All patients treated for retro-rectal tumours from 2012 to 2017 were included.

Out of 52 patients, 40 (77%) were women. The median age of patients at the time of surgery was 43 (19-76) years, and 30 (58%) were asymptomatic at the time of diagnosis. All tumours were visible on magnetic resonance imaging (MRI) prior to surgery. The sensitivity and specificity for predicting malignancy on preoperative imaging for retro-rectal tumours were 25% and 98%, respectively. Forty-four procedures (85%) were performed using the perineal approach. The median hospital stay was 3 (1-18) days. There was no 30-day postoperative mortality. Eleven (21%) patients developed postoperative complications, mostly surgical site infections. Twenty-nine tumours (56%) were benign tailgut cysts. Four (8%) tumours were malignant and were considered to be removed with a tumour-free resection margin. Local recurrent disease was detected on MRI in 14 (27%) patients at a median of 1.05 (range 0.78-1.77) years after primary surgery. Only the multi-lobular shape of the tumour was found to be an independent risk factor for recurrence (P = 0.030).

A preoperative MRI is mandatory in order to plan the surgical strategy for retro-rectal tumours. Symptomatic, solid, large tumours should be removed because of the risk of malignancy. Minor cystic lesions with thin walls as well as asymptomatic recurrences of benign tumours are suitable to be followed conservatively.