THE INCIDENCE OF SEMINOMA AND EXPRESSION OF CELL-ADHESION MOLECULE CD44 IN CRYPTORCHID BOYS AND INFERTILE MEN

Purpose: The incidence of seminoma in men with cryptorchid testes is a contentious issue among physicians. Nevertheless, a positive correlat ion has been shown between the susceptibility for seminoma in patients with the oligo-asthenoteratospermia syndrome and in those with crypto rchid testes. Materials and Methods: We histologically examined 5,231 biopsies from 3,867 patients, including 1,121 men with the oligo-asthe noteratospermia syndrome, 218 men with azoospermia and 2,528 boys with cryptorchidism. Testicular tissue embedded in Epon was analyzed by li ght microscopy, fluorometry, electron microscopy and immunohistochemis try. Cell adhesion molecule CD44 was detected using a monoclonal antib ody in all biopsies of patients suspected of having carcinoma in situ. Results: The incidence of seminoma was identical in boys with cryptor chidism and infertile men with the oligo-asthenoteratospermia syndrome but it was significantly higher than in the normal population. All bi opsies were analyzed by a single investigator, including 2,528 from 2, 403 cryptorchid boys and 2,322 from 1,339 infertile men. Seminoma was found in 4 cryptorchid boys of whom 3 had intra-abdominal testes. The incidence of seminoma in infertile men with the oligo-asthenoteratospe rmia syndrome was 6/1,121 (4 stage I and 2 stage II). Overall 10 semin omas were noted in 3,867 patients, including 1 in whom seminomas subse quently developed in both testes. Before the onset of puberty primordi al germ cells persisted in 7 of the 2,528 cryptorchid patients, althou gh no invasive seminomas were detected. An anti-CD44 monoclonal antibo dy was found to bind selectively to seminoma cells in the earliest sta ges of malignant transformation and metastasis, which to our knowledge represents the first reported incidence of CD44 expression associated with seminoma cells. Conclusions: The incidence of carcinoma in situ in patients with the oligo-asthenoteratospermia syndrome or cryptorchi dism was 0.27%. If the occurrence of primordial germ cells is consider ed, the overall incidence was 0.46% (17 of 3,659 cases). CD44 was expr essed in all seminoma cells as well as in all primordial germ cells. B ecause CD44 adhesion molecules are expressed in the earliest stages of seminoma development, anti-CD44 monoclonal antibody is an important n ew tool for positively identifying this type of neoplasm in all cases.