Müllerian Endometrioid Adenocarcinoma Arising from Colonic Endometriosis: Report of a case that presented with bowel obstruction

摘要

Gastrointestinal endometriosis-associated malignancies are rare and diagnostically challenging. Mullerian endometrioid adenocarcinoma is the most common and likely to be confused with a primary colonic adenocarcinoma due to their overlapping histological features. We present a case of mullerian endometrioid adenocarcinoma arising from colonic endometriosis in a 61-year-old woman who presented with bowel obstruction. The tumor had histological features remarkably simulating a primary colonic adenocarcinoma because of its transmural involvement of the sigmoid colon, colonization of the colonic surface epithelium and mesenteric lymph node metastasis. A high index of suspicion in conjunction with careful histological and immunohistochemical examination (CK7, CK20, CDX2, CD10, ER and PR immunostains) is important for establishing a correct diagnosis. Case History The patient, a 61-year-old woman, presented with vaginal bleeding, worsening nausea, vomiting and constipation over 10 days before admission. At the outside hospital, she was found to have bowel obstruction involving descending to sigmoid colon, confirmed by Barium enema imaging and flexible sigmoidoscopy, and a pelvic mass greater than 25 cm with MRI features consistent with uterine smooth muscle tumor. The patient had a past medical history of hypertension and chronic venous insufficiency of lower extremities. An elevated serum CA-125 level was also noted (110 U/ml, normal: <35 U/ml). She was transferred to the Gynecological Oncology Service at Yale-New Haven Hospital for total abdominal hysterectomy, bilateral salpingo-oophorectomy and rectosigmoid resection.At surgery, the uterus was found markedly enlarged with multiple leiomyomas. Extensive adhesions were noted between posterior aspect of the cervix and rectum. The large bowel was severely dilated from the ileocecal valve to the junction of the descending and sigmoid colon, where a 3.0 cm mass was noted with collapsed large bowel beyond this point. Small bowel, appendix, liver, pancreas, and bladder appeared unremarkable. Frozen sections demonstrated an “infiltrating adenocarcinoma, favor mullerian primary in the colon”. Subsequent pelvic lymph node dissection, omentectomy and peritoneal sampling were performed. Pathological Findings The uterus weighed 2800 grams and measured 17.0 x 17.0 x 15.0 cm. The endometrium was atrophic and its cavity was markedly distorted. There were multiple leiomyomas ranging from 0.6 to 11.0 cm involving submucosa and myometrium. The attached ovaries measured 4.0 x 2.5 x 0.7 cm on the right and 3.0 x 2.0 x 0.7 cm on the left. The surgically removed sigmoid colon demonstrated an obstruction site, 3 cm from the proximal resection margin, where a white tan retraction area (2.0 x 2.0 cm) on the serosa and a 2.5 x 1.5 x 1.5 cm white tan infiltrative mass lesion involving the colonic wall were found (figure 1A). The remaining colonic mucosa showed no evidence of ulceration or polyps.