Excision versus colorectal resection in deep endometriosis infiltrating the rectum: 5-year follow-up of patients enrolled in a randomized controlled trial

STUDY QUESTION: Is there a difference in functional outcomes and recurrence rate between conservative versus radical rectal surgery in patients with large deep endometriosis infiltrating the rectum 5 years postoperatively? SUMMARY ANSWER: No evidence was found that long-term outcomes differed when nodule excision was compared to rectal resection for deeply invasive endometriosis involving the bowel. WHAT IS KNOWN ALREADY: Functional outcomes of nodule excision and rectal resection for deeply invasive endometriosis involving the bowel are comparable 2 years after surgery. Despite numerous previously reported case series enrolling patients managed for colorectal endometriosis, long-term data remain scarce in the literature. STUDY DESIGN, SIZE, DURATION: From March 2011 to August 2013, we performed a two-arm randomized trial, enrolling 60 patients with deep endometriosis infiltrating the rectum up to 15 cm from the anus, measuring >20 mm in length, involving at least the muscular layer in depth, and up to 50% of rectal circumference. Among them, 55 women were enrolled at one tertial referral centre in endometriosis, using a randomization list drawn up separately for this centre. Institute review board approval was obtained to continue follow-up to 10 years postoperatively. One patient requested to stop the follow-up 2 years after surgery. PARTICIPANTS/MATERIALS, SETTING, METHODS: Patients underwent either nodule excision by shaving or disc excision, or segmental resection. Randomization was performed preoperatively using sequentially numbered, opaque, sealed envelopes, and patients were informed of randomization results. The primary endpoint was the proportion of patients experiencing one of the following symptoms: constipation (1 stool/>5 consecutive days), frequent bowel movements (≥3 stools/day), anal incontinence, dysuria or bladder atony requiring self-catheterization 24 months postoperatively. Secondary endpoints were values taken from 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). MAIN RESULTS AND THE ROLE OF CHANCE: Fifty-five patients were enrolled. Among the 27 patients in the excision arm, two were converted to segmental resection (7.4%). One patient managed by segmental resection withdrew from the study 2 years postoperatively, presuming that associated pain of other aetiologies may have jeopardized the outcomes. The 5 year-recurrence rate for excision and resection was 3.7% versus 0% (P = 1), respectively. For excision and resection, the primary endpoint was present in 44.4% versus 60.7% of patients (P = 0.29), respectively, while 55.6% versus 53.6% of patients subjectively reported normal bowel movements (P = 1). An intention-to-treat comparison of overall KESS, GIQLI, Wexner, USP and SF36 scores did not reveal significant differences between the two arms 5 years postoperatively. Statistically significant improvement was observed shortly after surgery with no further improvement or impairment recorded 1-5 years postoperatively. During the 5-year follow-up, additional surgical procedures were performed in 25.9% versus 28.6% of patients who had undergone excision or resection (P = 0.80), respectively. LIMITATIONS, REASONS FOR CAUTION: The presumption of a 40% difference concerning postoperative functional outcomes in favour of nodule excision resulted in a lack of power for demonstration of the primary endpoint difference. WIDER IMPLICATIONS OF THE FINDINGS: Five-year follow-up data do not show statistically significant differences between conservative and radical rectal surgery for long-term functional digestive and urinary outcomes in this specific population of women with large involvement of the rectum. STUDY FUNDING/COMPETING INTEREST(S): No specific funding was received. Patient enrolment and follow-up until 2 years postoperatively was supported by a grant from the clinical research programme for hospitals in France. The authors declare no competing interests related to this study. TRIAL REGISTRATION NUMBER: This randomized study is registered with ClinicalTrials.gov, number NCT01291576. TRIAL REGISTRATION DATE: 31 January 2011. DATE OF FIRST PATIENT’S ENROLMENT: 7 March 2011.