What condition would cause an elevation in both alpha-fetoprotein and human chorionic gonadotropin levels?

The elevation of both alpha-fetoprotein (AFP) and human chorionic gonadotropin (hCG) levels is characteristic of gestational trophoblastic disease. This condition encompasses a group of pregnancy-related tumors, such as hydatidiform mole and choriocarcinoma, which arise from the trophoblastic tissue related to pregnancy.

Gestational trophoblastic disease is notable for producing excess amounts of hCG due to the abnormal proliferation of trophoblastic cells. In addition to elevated hCG, AFP levels can also be increased in cases where there is an associated fetal component or in certain types of gestational trophoblastic disease, such as when there is a coexisting fetus or in some moles. This dual elevation can thus serve as an important diagnostic marker in the clinical practice of monitoring and evaluating these conditions.

While neural tube defects are associated with increased levels of AFP, they do not affect hCG levels. Multiple gestations can elevate hCG levels, but AFP may not be consistently elevated, as it depends on the gestational age and the individual circumstances of each pregnancy. Down syndrome screening typically involves measuring hCG and AFP, but usually presents as an atypical combination, not a simultaneous elevation characteristic of trophoblastic diseases