Value of five tumor markers (AFP, CEA, hCG, hPL and SP1) in diagnosis and staging of testicular germ cell tumors.

Serum levels of AFP, CEA, hCG, hPL and SP1 were measured by specific radioimmunoassays in 111 patients with testicular germ cell tumors. Seminomas, mature teratomas and "pure type" embryonal carcinomas, as well as the latter two types of tumor with seminomatous admixture, do not produce markers unless in advanced stages when they may do so (small amounts of hCP, hPL and SP1). Tumors composed of yolk-sac elements alone or mixed with embryonal carcinoma produce AFP: of syncytiotrophoblastic elements - hCG, hPL or SP1; and teratomas with differentiated structures - CEA. Compound tumors can produce any of the five markers. When present in serum after orchiectomy or lymphadenectomy, the markers are useful both in diagnosis of the tumor elements that metastasized and in staging; whereas their absence does not exclude regional or distant metastases which may contain only marker-negative elements, e.g., due to changes in tumor histology. Measurement of the serum levels of the markers informs about the remaining regional tumor elements or latent metastases and therefore is more useful than immunoperoxidase staining which provides information on the already dissected structures only.