Vascular Involvement: An Uncommon Histologic Finding of Rectal Endometriosis

Deep infiltrating endometriosis frequently affects the rectosigmoid region. It clinically presents as a chronic painful condition affecting women in their reproductive time. Here, we present a case of a 28-yr-old female patient who had a history of dysmenorrhea, dyspareunia, chronic abdominal and pelvic pain, and constipation secondary to rectal wall endometriosis. Microscopic examination of the resected rectal segment showed endometriosis with vascular and lymph node involvement. Vascular involvement is an uncommon histologic finding that may raise concern for potential malignancy. The aim of this report is to alert pathologists and physicians about this infrequent pitfall that can be mistaken for a neoplastic process and to discuss the underlying pathophysiology of vascular involvement by endometrial tissue in otherwise benign conditions.