Gestational trophoblastic neoplasms are malignant lesions that arise from placental villous and extravillous trophoblast. Four clinicopathologic conditions make up this entity: invasive mole (IM), choriocarcinoma (CCA), placental-site trophoblastic tumor (PSTT), and epithelioid trophoblastic tumor (ETT). IM and CCA, which make up the majority of these tumors, are highly responsive to chemothera...