derives from/develops from chorion trophoblast choriocarcinoma cell A cell of an epithelial malignancy of trophoblastic cells, formed by the abnormal proliferation of cuboidal and syncytial cells of the placental epithelium, without the production of chorionic villi. Almost all cases arise in the uterus, developing from hydatidiform mole, following abortion, or during normal pregnancy. The remainder occur in ectopic pregnancies and genital (ovarian and testicular) and extragenital teratomas. BTO:0001576 BrendaTissueOBO chorioblastoma cell chorioepithelioma cell chorionic carcinoma cell chorionic epithelioma cell syncytioma malignum