<prompt> Which of the following is not trophoblast related:ChoriocarcinomaH. molePlacental Site tropboblast tumorChorioangioma  <response>: Ans-D Chorioangiomas the most common tumor of the placenta It is a benign vascular tumor of placental origin and is usually found incidentally. They are thought to arise as a malformation of the primitive angioblastic tissue of the placenta. The angiomas are perfused by the fetal circulation. Therefore when they are large, they may represent a significant impediment to fetal cardiac activity. This angiomasmay also sequester platelets and can, in turn, give a fetal thrombocytopenia They can also cause the increase in levels of maternal serum alpha-fetoprotein MSAFP and may prompt sonographic evaluation.Modified WHO Classification of Gestational Trophoblastic DiseaseMolar lesionsNonpolar lesions Hydatidiform mole Complete Partial Invasive mole Choriocarcinoma Placental site trophoblastic tumor Epithelioid trophoblastic tumor Choriocarcinoma: A morphologic term applied to a highly malignant type of trophoblastic neoplasia in which both the cytotrophoblast and syncytiotrophoblast grow in a malignant fashion. Chorionic villi are absent. These tumors tend to be hemorrhagic and necrotic H. Mole: A placental abnormality involving swollen placental villi and trophoblastic hyperplasia with loss of fetal blood vessels. There are two types: partial and complete. Partial: A molar pregnancy with swelling of all placental villi. Fetal tissues are absent. Complete: A molar pregnancy with some normal and some swollen villi plus fetal, cord, andor amniotic membrane elements. Placental-Site Trophoblastic Tumor A rare type of GTD arising in the uterus that secretes human placental lactogen and human chorionic gonadotrophin HCG. NOTE: Persistent abnormal bleeding following normal pregnancy, abortion, or ectopic pregnancy should lead to a consideration of the diagnosis of GTD. The finding of pulmonary nodules on chest radiograph after normal pregnancy suggests GTD. 