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Seminomas develop from the sperm-producing germ cells of the testicle. The 2 main subtypes of these tumors are classical (or typical) seminomas and spermatocytic seminomas.
Classical seminoma: More than 95% of seminomas are typical. These usually occur in men when they are between their late 30s and early 50s.
Spermatocytic seminoma: This rare type of seminoma tends to occur in older men. The average age of men diagnosed with spermatocytic seminoma is about 55. Spermatocytic tumors tend to grow more slowly and are less likely to spread to other parts of the body than classical seminomas.
Some seminomas can increase blood levels of a protein called human chorionic gonadotropin (HCG). HCG can be detected by a simple blood test and is considered a tumor marker for certain types of testicular cancer. It can be used for diagnosis and to check for response to therapy.
Clinical trials are research studies that evaluate a new medical approach, device, drug, or other treatment. As a Stanford Health Care patient, you may have access to the latest, advanced clinical trials.
Open trials refer to studies currently accepting participants. Closed trials are not currently enrolling, but may open in the future.