ABSTRACT
BACKGROUND: Placental site trophoblastic tumor (PSTT) is tumor of intermediate trophoblast, seen commonly in reproductive age group. CASE: A 63-year-old postmenopausal woman presented with vaginal discharge, occasional bleeding and a large uterine mass suspicious of malignancy. The uterus ruptured during hysterectomy. A large, necrotic and hemorrhagic tumor was seen in the endometrial cavity infiltrating through the myometrium into serosa. The tumor cells were large pleomorphic, polygonal with variable mitosis. The histological differential diagnosis included choriocarcinoma, epithelioid trophoblastic tumor, epithelioid leiomyosarcoma and poorly differentiated carcinoma. The tumor cells were positive for cytokeratin and beta-hCG and negative for smooth muscle antigen and HMB-45. The final histological diagnosis was PSTT. CONCLUSION: PSTT is rare in postmenopausal females. It is difficult to diagnose clinically as well as histologically.
