Cyclic Hematochezia: A Sign of Intestinal Endometriosis? An Evaluation by Magnetic Resonance Imaging and Colonoscopy

Purpose Intestinal bowel endometriosis is reported in up to 37% of women with proven endometriosis. The aim of this study was to evaluate by colonoscopy and magnetic resonance imaging, patients suspected of deep infiltrating endometriosis (DIE) including the bowel wall that presented with cyclic hematochezia. Methods Twenty-four patients with cyclic hematochezia were retrospectively analyzed on colonoscopic features of colonoscopy, corresponding biopsy data, and outcome of magnetic resonance imaging evaluation. Fifteen out of 24 patients underwent bowel resection because of insufficient response to hormonal treatment (N=14) or obstructive ileus (N=1). Outcome of surgery and histologic examination of the resected specimens were evaluated. Results Colonoscopy proved intestinal endometriosis in only one out of 24 (4%) patients with cyclic hematochezia. In 13 out of 15 bowel resections endometriosis was found at histopathology. The location and dimension of lesions during surgery correlated well with magnetic resonance imaging findings. However, magnetic resonance imaging revealed a limited capacity to detect luminal narrowing of the bowel. Conclusions This study shows that colonoscopic findings of bowel endometriosis are aspecific. Colonoscopy, an invasive investigation, should therefore not be performed to diagnose endometriosis infiltrating the bowel wall. Magnetic resonance imaging provides good diagnostic work-up and in selected patients a roadmap to surgery.