Objectives: The pathologic complexity of the testicular tumor makes it difficult to demonstrate exactly the relationship between the impaired spermatogenesis in patients with a testicular tumor and the serum level of the human chorionic gonadotropin beta subunit (beta-hCG). Therefore, we performed quantitative evaluation of spermatogenesis in ipsilateral and contralateral testicular tissues of seminoma to simplify the relation pathologically and endocrinologically and to demonstrate the exact correlation between spermatogenesis and serum beta-hCG levels.
Methods: Fifty-three biopsy specimens from ipsilateral and contralateral testicular tissues of seminoma were analyzed histologically. The quantitative evaluation of spermatogenesis was performed by the mean Johnsen's score count (MJSC). Beta-hCG expression in seminoma was examined immunohistochemically. Serum beta-hCG, testosterone, estradiol, luteinizing hormone, and follicle-stimulating hormone levels were analyzed before orchiectomy.
Results: A significant linear relationship (r = -0.82; P <0.005) was found between the serum level of beta-hCG and the MJSC in contralateral testicular tissues but not in ipsilateral ones, although the suppression of spermatogenesis was observed in both sides without suppression of luteinizing hormone and/or follicle-stimulating hormone production.
Conclusions: A clearcut fall in the MJSC with an associated rise in the serum level of beta-hCG was demonstrated in the contralateral testicular tissues but not in the ipsilateral ones of seminoma. It seems most likely that serum beta-hCG suppresses spermatogenesis in both ipsilateral and contralateral testicular tissues without the suppression occurring through the hypothalamus-pituitary-gonadal system, and also that some less well recognized factors affect spermatogenesis, making the relation between serum beta-hCG and MJSC obscure in ipsilateral testicular tissues.