A Case Report of Sigmoid Endometriosis in a Postmenopausal Woman Requiring Bowel Resection

Introduction: Endometriosis is the presence of endometrial glands and stroma in ectopic locations outside the uterine cavity. Colonic endometriosis is rare and endometriosis of any type is uncommon in postmenopausal women.

Presentation of Case: A seventy-six-year-old lady presented with altered bowel habit. She had no known history of symptomatic endometriosis during her reproductive years. A computed tomography colonography was performed after a failed colonoscopy. This showed a lesion in the wall of the sigmoid colon. She underwent a laparoscopic assisted anterior resection and anastomosis. The histopathology showed mass forming endometriosis in the wall of the sigmoid colon.

Discussion: Deep infiltrating endometriosis is defined as a solid mass situated deeper than 5 mm under the peritoneum. The prevalence of deep infiltrating endometriosis involving the bowel has been reported to be 5.3–12% of women affected by endometriosis. Deep infiltrating endometriosis involving the bowel is most frequently localised in the rectum and sigmoid colon. Other bowel localisations are relatively rare. Endometriosis in postmenopausal women is also rare.

Conclusion: Diagnosis of colonic endometriosis preoperatively is difficult and usually leads to a bowel resection as malignancy cannot be excluded. The diagnosis is usually established on histological examination. Colonic endometriosis in postmenopausal women is rare and difficult to diagnosis but should be considered in cases of distal bowel obstructions or abnormal radiological findings that cannot be biopsied by colonoscopy.