Predictive factors of functional outcomes after the surgery of rectal endometriosis are not well identified. Our recent randomized trial did not find significant differences between functional outcomes in patients managed by radical or conservative rectal surgery.

To identify preoperative factors which determine functional outcomes of surgery in patients with rectal endometriosis.

We performed a cohort study on the population of a 2-arm randomised trial, from March 2011 to August 2013. Patients were enrolled in three French university hospitals and had either conservative surgery by shaving or disc excision, or radical rectal surgery by segmental resection. The primary endpoint was the proportion of patients experiencing one of the following symptoms: constipation, frequent bowel movements, anal incontinence, dysuria or bladder atony requiring self-catheterisation 24 months postoperatively. Secondary endpoints were the values of the Knowles-Eccersley-Scott-Symptom Questionnaire (KESS), the Gastrointestinal Quality of Life Index (GIQLI), the Wexner scale, the Urinary Symptom Profile (USP) and the Short Form 36 Health Survey (SF36). A logistic regression model based on backward selection was used to screen for baseline factors that could impact the primary endpoint. A generalized estimating equations model for repeated measures was used to assess whether a trend could be observed over the follow-up period as regards gastrointestinal and quality of life scores.

60 patients with deep endometriosis infiltrating the rectum were managed by conservative surgery (27 cases) and segmental colorectal resection (33 cases). The primary endpoint was recorded in 26 patients (48.1% for conservative surgery vs. 39.4% for radical surgery, OR = 0.70, 95% CI 0.22–2.21). There was a significant improvement in values of all gastrointestinal, quality of life and urinary scores after surgery. Comparing patients with KESS scores < 10 (reference) to those with scores between 10 and 17 (OR = 2.1, 95%CI 0.4–12.2), as well as those with scores >17 (OR = 11.1, 95%CI 2.2–20.5), revealed that the odds to record the primary endpoint are significantly higher in the latter group. Trend analyses suggest that the odds of an elevated KESS score are significantly higher at baseline than at 6 months, but significantly lower after 12 months.

Patients with severe preoperative constipation are less likely to achieve normal bowel movements after surgery for rectal endometriosis, using either radical or conservative rectal procedures.