gestational trophoblastic neoplasia

Gestational trophoblastic disease, usually referred to as a mole, is a very rare abnormality of pregnancy in the reproductive female that involves abnormal trophoblast proliferation.It is the result of a (purely chance) genetic error during the fertilization process that in turn causes the growth of abnormal tissue (which is not an embryo) within the uterus. The growth of this material is disproportionately rapid when compared to normal fetal growth.
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Neoplasia /neo·pla·sia/ the formation of a neoplasm. cervical intraepithelial neoplasia dysplasia of the cervical epithelium, often premalignant, [more]Gestational trophoblastic neoplasia - Community and Resources

A rare cancer in women of childbearing age in which cancer cells grow in the tissues that are formed in the uterus after conception. Also called gestational trophoblastic disease, gestational trophoblastic tumor, molar pregnancy, or choriocarcinoma.