Introduction A malignant tumor arising from the trophoblast Most commonly follow non-complete removal of hydatidiform mole may also result following normal pregancy or abortion Prognosis rapidly invades uterine wall metastasizes hematogenously one of several rare carcinomas to do so lungs are most common site gestationally derived masses have good prognosis non-gestationally derived masses have worse prognosis Presentation Symptoms vaginal bleeding Physical exam uterine enlargement Evaluation Labs high β-hCG Chest x-ray check for lung metastasis Biopsy avillous proliferation of cytotrophoblasts and syncytiotrophoblasts Treatment Pharmacologic chemotherapy