A Case of Extensive Pelvic Endometriosis and Associated Sigmoid Polyp: A Case Report

Abstract

Gastrointestinal system is the commonest site of extragenital endometriosis. Its clinical manifestations are nonspecific and lacks etiological manifestations. Differentiation of colorectal endometriosis from malignancy is often difficult and leads to misdiagnosis. We report a case of extensive pelvic endometriosis involving uterus, ovaries and sigmoid colon, presented as colonic polyp. A 39-year-old woman was referred to Central hospital, Dhaka with abnormal uterine bleeding, left lower abdominal pain, chronic constipation and per rectal bleeding. Colonoscopy showed a polypoid lesion in sigmoid colon. Biopsy was taken from the lesion. The Magnetic Resonance Imaging (MRI) of pelvis was reported as diffuse uterine adenomyosis, bilateral ovarian endometriotic cysts, extensive adhesion with omentum and bowel loops, circumferential sigmoid colonic growth forming an amalgamated pelvic mass (4 × 1.4 cm) and moderate luminal narrowing. Laparoscopic high anterior resection with ileostomy with Total Abdominal Hysterectomy (TAH) and Bilateral Salpingo-Oophorectomy (BLSO) was performed. Endometriosis was diagnosed histopathologically in both specimens of the sigmoid polypoid mass. Periodic Acid-Schiff (PAS) stain was negative in endometrial glandular cells. Immunohistochemistry (CK7, CK20, vimentin, ER) were also performed. CK7, vimentin and ER antibodies were positive, whereas CK20 antibody was negative in endometrial gland and stroma, which further confirmed the diagnosis. This case merits attention because a preoperative diagnosis of colorectal endometriosis is often misleading. The histopathological, clinical, sonographic or radiological findings can easily mimic the features of malignancy. It also highlights the importance of maintaining a broad differential diagnosis and utilizing a multidisciplinary team in the management of a colorectal mass in women of reproductive age groups.