Alpha-fetoprotein, prealbumin, albumin, alpha-1-antitrypsin and transferrin as diagnostic and therapeutic markers for endodermal sinus tumors.

According to Gitlin, alpha-fetoprotein (AFP), albumin, prealbumin, alpha-1-antitrypsin and transferrin are normal products of the human yolk sac. They are expected to reappear in human endodermal sinus tumor (yolk sac tumor). The synthesis of alpha-fetoprotein and other serum proteins by human endodermal sinus tumor was studied in the culture cells and in the tumor tissue transplanted into nude mice. The results gave evidences of synthesis of some of these proteins including alpha-fetoprotein and alpha-1-antitrypsin. Serum concentrations of these proteins were studied in eight children having endodermal sinus tumors. Serum AFP levels were abnormally high in all cases, whereas concentrations of other serum proteins were almost within normal ranges. This might be simply reflected by the fact that pre-albumin, albumin, alpha-1-antitrypsin, and transferrin are already present in large quantities in sera of normal subjects while alpha-fetoprotein is present only in a negligible quantity. Alpha-fetoprotein, as a diagnostic and therapeutic marker of endodermal sinus tumor, showed good correlation to the tumor growth. Serum AFP concentrations declined almost to 0 ng/ml with a half-life of 4 days when surgical removal was complete, whereas serum AFP decreased only to 100-200 ng/ml with radiation and chemotherapy alone.