A.V. Sakalo

Testicular intraepithelial neoplasia (TIN) in the pathogenesis of germ cell testicular tumors (review and the results of own research)

Testicular germ cell tumors (TGCT, seminoma, embryonal carcinoma, teratoma, yolksactumors) indevelopmen thave a common precursor - intratubular germ cell neoplasia (IGCN). Investigation in gene expression of recent years, proving the similarities between IGCN and embryonic stem cells and confirm the theory of IGCN origin from fetal gonocytes in vitro. Frequently IGCN associated with various components of testicular dysgenesis syndrome (TGCT, cryptorchidism, some forms of decrease spermatogenesis) also show prenatal origin of IGCN. Diagnosis for preinvasive stage of tumor can minimize the side effects of additional treatment. The presence of IGCN may be suspected in cases of extragonadal localization of TGCT, cryptorchism and in some forms of infertility (testicular atrophy and microlithiasis). Today testicular biopsy is the only accurate method of IGCN diagnosis. The principles of IGCN treatment are debated: surveillance, radiation to the affected testicle, orchiectomy and chemotherapy. It is believed that about 5% of patients with TGCT have IGCN in contralateral testicle, so perhaps it is appropriate for diagnostic purposes to offer contralateral testicular biopsy during orchiectomy. Further studies should reveal the reasons for the increase in the incidence of TGCT and suggest methods of non-invasive diagnosis of IGCN.