Genetic aspects of gestational trophoblastic diseases: a general overview with emphasis on new approaches in determining genetic composition.

All gestational trophoblastic tumors are derived from a fertilization event. In the hydatidiform moles, varying degrees of excess paternal DNA lead to varying histopathologic forms of these tumors. The placental site trophoblastic tumors and the choriocarcinomas may follow normal pregnancy, abortions and hydatidiform moles, and, thus evince a wide range of genetic compositions reflecting their gestation of origin. Advances in molecular biological diagnoses now allow for the determination of the gestational or non-gestational origin of trophoblastic tumors, and, may well provide fantastic new insights into the biology of these unusual tumors.