Testicular biopsy in the study of male infertility: its current usefulness, histologic techniques, and prospects for the future.

Testicular biopsy has been widely used for the diagnosis of male infertility for more than three decades. During that time, with advances in cytogenetics, radioimmunoassay, and endocrinology, the role of testicular biopsy has changed. Testicular biopsy is still useful in the diagnosis of azoospermic and oligospermic males without stigmata of gonadotropic insufficiency or Klinefelter's syndrome. A classification and description is presented of pathologic changes in the testis as seen on testicular biopsy by light microscopy. The present rationale for testicular biopsy in infertility, the processing and staining of histologic material, and the role of testicular biopsy in infertility and infertility related situations, including cryptorchidism, malignant disease, and chemotherapy related changes, are discussed. Further understanding of testicular function and disease will depend upon the correlation of histologic and ultramicroscopic changes, immunohistologic localization of hormones, and epidemiologic and endocrinologic data.