The value of serial measurement of both human chorionic gonadotropin and alpha-fetoprotein for monitoring germinal cell tumors.

Quantitative serial serum measurements of human chorionic gonadotropin (hCG) and alpha-fetoprotein (AFP) levels using sensitive double-antibody radioimmunoassays were performed in nine patients with germinal cell tumors before and during treatment. The sera of eight of the nine were found to have a hCG marker and five of the nine an AFP marker. The sera of four patients were found to have both. Serial serum levels of hCG, of AFP, or both were useful for monitoring disease activity during therapy in all nine patients. In two patients tumor masses failed to diminish during chemotherapy, but the tumor markers fell appropriately. At surgery one patient had a mature teratoma, the other a mature teratoma with a microscopic focus of an embryonal cell tumor. In one patient tumor reactivation was reflected by the emergence of only one of two previously elevated tumor markers. One patient had a rise in hCG, another a rise in both markers coincident with recurrence of tumor. Serial measurements of AFP and hCG are useful for following the response to therapy of germinal tumors, and can assist in making therapeutic decisions.