Arch Gynecol Obstet (2008) 277:185–187 DOI 10.1007/s00404-007-0454-x 123 CASE REPORT Multilocular intrauterine cystic mass, atypical presentation of endometrial stromal sarcoma: a case report Reda A. Ali · El-Said Abd El-Hady · Mostafa El-Zayat Received: 4 June 2007 / Accepted: 17 August 2007 / Published online: 27 November 2007  Springer-Verlag 2007 Abstract Endometrial stromal sarcoma (ESS) is a rare neoplasm comprising only 0.2% of all uterine malignancies and 15–26% of primary uterine sarcomas. Pathology of the tumor was described as soft, Xeshy, smooth polypoidal mass, which may protrude in the uterine cavity. This case report, represent atypical presentation of ESS as multilocu- lar cystic intrauterine mass, which can be misdiagnosed as multilocular ovarian cyst. Introduction Endometrial stromal sarcoma (ESS) is a rare neoplasm comprising only 0.2% of all uterine malignancies and 15–26% of primary uterine sarcomas [1]. It is classi Wed into two distinct subtypes, low-grade and high-grade, based on diVerences in morphological atypia and proliferative activity [2]. High-grade ESS has an aggressive nature, whereas low-grade ESS, which was formerly called endo- lymphatic stromal myosis, is a slow growing tumor with much better prognosis [3]. Pathology of the tumor was described as soft, Xeshy, smooth polypoidal mass, which may protrude inside the uterine cavity [4]. Occasionally, cystic areas containing altered blood were present within the mass. Several of the endometrial glands were cystically dilated and contained altered blood within the lumen [5]. Case report A 53-years-old, postmenopausal woman for 2 years was presented with lower abdominal pain and postmenopausal bleeding for 2 months. Abdominal and bimanual pelvic examination revealed a cystic pelviabdominal swelling, occupying the suprapubic region, mobile from side to side. Uterus could not be felt separate from the mass. Cervix was healthy and adnexae could not be palpated. Transabdominal ultrasound (Fig. 1), revealed multilocu- lar cystic swelling 15 £ 15 cm with thick septa and solid parts. This was misdiagnosed as a malignant ovarian tumor. Cystoscopy, colonoscopy, chest X-ray, and bone survey were free and CA 125 was 6 IU/ml. Laparotomy was done through a midline exploratory incision. Abdominal exploration revealed normal ovaries and there was no ascites. The uterus was symmetrically enlarged (Fig. 2), about 20 £ 15 cm and soft in consis- tency. Total abdominal hysterectomy and bilateral sal- pingo-oophorectomy were done. The uterine cavity was opened and a multilocular cystic swelling 15 £ 15 cm Wlling the uterine cavity and contain- ing clear serous Xuid was identiWed. There was a plane of cleavage between the mass and the myometrium (Figs. 3 and 4). Histopathology revealed low-grade stromal cell sarcoma of the endometrium (Fig. 5) The myometrium was not inWl- trated and the cervix and both ovaries were normal. Discussion Endometrial stromal sarcoma (ESS) is a rare neoplasm comprising only 0.2% of all uterine malignancies and R. A. Ali (&) · E.-S. A. El-Hady · M. El-Zayat Department of Obstetrics and Gynaecology, Faculty of Medicine, Mansoura University, Mansoura, Egypt e-mail: redaelshouky@hotmail.com