Low-Grade Endometrial Stromal Sarcoma with Intravenous and Intracardiac Extension: A Case Report

Abstract

Background: Low-grade endometrial stromal sarcoma (ESS) is rare mesenchymal neoplasm, which has an indolent history with late recurrences. ESS usually spread through the lymph nodes and venous system but very seldom involve large vessels or the heart.Case presentation: A 38-year-old Chinese woman was admitted to our department due to pelvic mass found on physical examination. The superior and inferior vena cava CT angiography (CTA) showed an enlarged uterine as well as low density image in the left internal iliac vein, the left common iliac vein, the inferior vena cava, the left renal vein adjacent to the heart and the right atrium, with a range of 110*16mm. The filling defect of right atrium was about 30*14mm. The three-dimensional computed tomography reconstruction showed that the mass originated from the uterine and invaded into the reproductive vein, subsequently extended along the inferior vena cava to the right atrium. Needle biopsy of the pelvic mass was performed and the tissue indicates smooth muscle. The preoperative diagnosis was intravascular leiomyomatosis and the patient underwent radical resection: thrombectomy and total hysterectomy with bilateral salpingo-oophorectomy. Postoperative histopathology revealed low grade endometrial stromal sarcoma. Microscopically, the tumors in both original uterine lesions and intravascular and intracardiac metastases shared morphologic features characterized by neoplastic cells similar to proliferative-phase endometrial stromal cells, in which small spiral artery differentiation was recognized and tumor tissue showed invasive growth pattern by inserting into the surrounding smooth muscle. Immunohistochemistry showed tumor cells were reactive to Estrogen Receptor, Progesterone Receptor,CD10. Primary uterine foci showed cyclin D1(5%+) and Ki-67(20%+),whereas metastatic lesions of the intracardiac and the intravascular component identified cyclin D1(negative) and Ki-67(2%+). The patient is alive without evidence of recurrence 3 months after surgery.Conclusions: Distant metastasis of low-grade endometrial stromal sarcoma is rare, especially involving large vessels or the heart. This case demonstrates that malignant tumor metastasis should be considered as a differential diagnosis of intracardiac and intravascular masses. The treatment rely on multidisciplinary cooperation.