Which of the following changes would be most consistent with the diagnosis of choriocarcinoma?

Gestational trophoblastic disease may involve hydatidiform mole, choriocarcinoma, or placental trophoblastic tumor. Trophoblastic tissue produces B-HCG and thus B-HCG is elevated in all these conditions. AFP is increased in neural tube defect setting when screening at 15-18 weeks gestation. AFP may be decreased in Down syndrome.