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

Aim: 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.

Materials and methods: 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.

Results: 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.

Conclusion: 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.