Published online Apr 28, 2015. doi: 10.3748/wjg.v21.i16.4997
Peer-review started: October 15, 2014
First decision: December 2, 2014
Revised: December 20, 2014
Accepted: February 12, 2015
Article in press: February 13, 2015
Published online: April 28, 2015
AIM: To evaluate the accuracy of colonoscopy for the prediction of intestinal involvement in deep pelvic endometriosis.
METHODS: This prospective observational study was performed between September 2011 and July 2014. Only women with both a clinical and imaging diagnosis of deep pelvic endometriosis were included. The study was approved by the local ethics committee and written informed consent was obtained in all cases. Both colonoscopy and laparoscopy were performed by expert surgeons with a high level of expertise with these techniques. Laparoscopy was performed within 4 wk of colonoscopic examination. All hypothetical colonoscopy findings (eccentric wall thickening with or without surface nodularities and polypoid lesions with or without surface nodularities of endometriosis) were compared with laparoscopic and histological findings. We calculated the sensitivity, specificity, positive predictive value and negative predictive value for the presence of colonoscopic findings of intestinal endometriosis.
RESULTS: A total of 174 consecutive women aged between 21-42 years with a diagnosis of deep pelvic endometriosis who underwent colonoscopy and surgical intervention were included in our analysis. In 76 of the women (43.6%), intestinal endometrial implants were found at surgery and histopathological examination. Specifically, 38 of the 76 lesions (50%) were characterized by the presence of serosal bowel nodules; 28 of the 76 lesions (36.8%) reached the muscularis layer; 8 of the 76 lesions (10.5%) reached the submucosa; and 2 of the 76 lesions (2.6%) reached the mucosa. Colonoscopic findings suggestive of intestinal endometriosis were detected in 7 of the 174 (4%) examinations. Colonoscopy failed to diagnose intestinal endometriosis in 70 of the 76 women (92.1%). A colonoscopic diagnosis of endometriosis was obtained in all cases of mucosal involvement, in 3 of 8 cases (37.5%) of submucosal involvement, in no cases of muscularis layer involvement and in 1 of 38 cases (2.6%) of serosa involvement. The sensitivity, specificity, positive predictive and negative predictive values of colonoscopy for the diagnosis of intestinal endometriosis were 7%, 98%, 85% and 58%, respectively.
CONCLUSION: Being an invasive procedure, colonoscopy should not be routinely performed in the diagnostic work-up of bowel endometriosis.
Core tip: Endometriosis is common gynecological condition that in a substantial number of cases injures intestinal tissue and causes remarkable morbidity among affected individuals. A surgical approach is still the most effective, but preoperative assessment is often challenging even for expert physicians and requires several diagnostic techniques for a clear definition of the location and extent of endometrial implants. The aim of the present study was to evaluate the role of colonoscopy in the diagnostic work-up of bowel endometriosis.