Here is another example of seminoma of the testis. A small rim of remaining normal testis appears at the far right. The tumor is composed of lobulated soft tan to brown tissue. Laboratory testing can aid in diagnosis, staging/prognosis, and monitoring of therapy and recurrence of testicular germ cell neoplasms. The serum markers of greatest value include: lactate dehydrogenase isoenzyme 1 (LD1), alpha-fetoprotein (AFP), and human chorionic gonadotropin (HCG). The highest stage has the highest LD1.