NCI Dictionary of Cancer Terms
The NCI Dictionary of Cancer Terms features 8,442 terms related to cancer and medicine.
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- hydatidiform mole
- listen (HY-duh-TIH-dih-form...)
- A slow-growing tumor that develops from trophoblastic cells (cells that help an embryo attach to the uterus and help form the placenta) after fertilization of an egg by a sperm. A hydatidiform mole contains many cysts (sacs of fluid). It is usually benign (not cancer) but it may spread to nearby tissues (invasive mole). It may also become a malignant tumor called choriocarcinoma. Hydatidiform mole is the most common type of gestational trophoblastic tumor. Also called molar pregnancy.