Lymphangioleiomyomatosis of the uterus simulating high-stage endometrial stromal sarcoma.

Symptomatic uterine lymphangioleiomyomatosis (LAM) simulating high-stage uterine sarcoma in a patient with tuberous sclerosis complex is reported. A 49-year-old female presented with abdominal pain and anemia. Preoperative workup revealed a uterine mass and a large amount of peritoneal free fluid and possible metastatic implant along the lateral edge of the liver. The patient also had a large right pleural effusion. A fungating anterior uterine fundal mass with apparent perforation and intraabdominal hemorrhage was found on laparotomy. A portion of the mass was excised and initially interpreted as an endometrial stromal sarcoma. Microscopic examination revealed multiple vascular epithelioid smooth muscle proliferations in the uterus and serosal surface of the fallopian tube and periaortic lymph node lymphangioleiomyomas. The uterine, fallopian tube, and nodal lesions were positive for smooth muscle actin, desmin, and HMB-45, findings characteristic of LAM. Additional examination of the patient revealed stigmata of tuberous sclerosis complex. Although uterine LAM is uncommon, it may be associated with pelvic and/or abdominal symptoms and may simulate a primary uterine mesenchymal neoplasm.