Description
The term gestational trophoblastic disease (GTD) describes a range of pathologies derived from the villous trophoblasts of the placenta. These include benign entities such as partial and complete hydatidiform mole as well as invasive cancers such as gestational choriocarcinoma, placental site trophoblastic tumors, and epithelioid trophoblastic tumors. Collectively, the malignant forms of GTD are known as gestational trophoblastic neoplasia (GTN). The risk of GTN following a complete molar pregnancy ranges between 8-25%. Low risk patients are expected to have a high likelihood of response to single agent chemotherapy with methotrexate or actinomycin D, but the incidence of resistance to single agent chemotherapy among low risk patients remains 25-50%.