condition in which abnormal cells grow inside the uterus
from tissue that forms after conception (the joining of
sperm and egg). This tissue is made of trophoblastic cells,
which normally surround the fertilized egg in the uterus
and help connect the fertilized egg to the wall of the
uterus. These cells also form part of the placenta (the
organ that passes nutrients from the mother to the fetus).
Most gestational trophoblastic diseases are benign (not
cancer) and do not spread, but some types are malignant
(cancer) and spread to nearby tissues or other parts of the
body. The two main types of gestational trophoblastic diseases
are hydatidiform mole and choriocarcinoma. Also called gestational trophoblastic tumor, GTD, and GTT.