Pathology of germ cell tumors of the testis.

Testicular germ cell tumors form a complex group of interrelated entities. Problems of nomenclature remain, but there does appear to be a close agreement between the major classifications in use. The identification of clinically useful markers for certain germ cell testicular tumors has provided a major impetus in this field. Information gained from the study of these markers has promoted an understanding of the histogenesis of germ cell tumors, has improved standard nomenclature, and has stimulated progress in patient care. Radioimmunoassay techniques are now frequently used to measure beta-human chorionic gonadotrophin and alpha-fetoprotein levels in evaluating the clinical course of patients with nonseminomatous germ cell tumors of the testis. It is hoped that the use of these markers will permit earlier detection of tumor recurrence, prompt treatment, and an improved survival rate. The knowledge of the production of alpha-fetoprotein by the human yolk sac has further refined tumor classification. It is against this general background that we have outlined the standard pathology of germ cell tumors of the testis.