Deep endometriosis muscular infiltration of the bowel wall: correlation between MRI and histopathology

To assess the correlation between magnetic resonance imaging (MRI) and histopathology for predicting muscular infiltration of endometriosis in the bowel wall in patients undergoing colorectal resection.

All consecutive patients who underwent colorectal surgery for deep endometriosis (DE) with a preoperative MRI in a single tertiary care referral hospital between 2001 and 2019 were included in a prospective cohort. MRI images were revised by a single blinded radiologist. The MRI results regarding the infiltration depth (serosal, muscular, submucosal, or mucosal) and lesion expansion of DE were compared to histopathology.

A total of 84 patients were eligible for evaluation. A sensitivity of 89% and positive predictive value of 97% was shown for predicting muscular involvement of the bowel wall.

This study showed that MRI is valuable in predicting the involvement of the muscular layer of the colorectal wall. Therefore, in patients with symptomatic pelvic bowel endometriosis MRI is a useful tool in guiding the extent of colorectal surgery.