Testicular cancer occurs most often in younger men. It is the most-often diagnosed cancer in men between ages 20 and 34. However, it accounts for only 1% of all cancers that occur in men. When testicular cancer is detected early, there is a nearly 99% chance for successful treatment. Approximately 8,500 new cases of testicular cancer are diagnosed each year, and about 350 men, or less than 5%, die of the disease.
The testicles (also called testes) are a pair of male sex glands that are in a sac-like pouch (the scrotum) under the penis. They produce and store sperm and also are the body’s main source of male hormones. These hormones control the development of the reproductive organs and male characteristics.
Testicular cancer occurs when cells in the testicles grow and multiply uncontrollably, damaging surrounding tissue and interfering with the normal function of the testicle. If the disease spreads, it is still called testicular cancer.
Testicular Cancer Types
There are two basic types of testicular cancer, each with subtypes:
Germ cell tumors occur in the cells that produce sperm. Tumor types include:
Seminomas, the type found most often, are responsible for half of testicular cancer cases. They are generally slow growing and responsive to treatment.
Nonseminomas tend to grow and spread faster than seminomas. Tumor types include:
- Embryonal carcinoma (about 20% of testicular cancers)
- Yolk sac carcinoma (most often occurs in infants and young boys)
- Choriocarcinoma, a rare and extremely aggressive cancer
Stromal tumors occur in the testicular tissue where hormones are produced. Stromal tumor types include:
- Leydig cell tumors, which occur in cells that produce male sex hormones
- Sertoli cell tumors, which occur in cells that nourish germ cells
Testicular Cancer Risk Factors
Anything that increases your chance of getting testicular cancer is a risk factor. These include:
- Age: Most cases occur between the ages of 15 and 40, and testicular cancer is the type of cancer found most often in men ages 20 to 34.
- Race: White men are five to 10 times more likely to develop testicular cancer than men of other races.
- Family or personal history of testicular cancer
- Undescended testicle (cryptorchidism): Men with testicles that did not move down into the scrotum before birth are at increased risk. Men who had surgery to correct this condition are still at high risk of testicular cancer.
- Abnormal testicular development
- Klinefelter's syndrome: A sex chromosome disorder characterized by low levels of male hormones, sterility, breast enlargement, and small testes
- Human immunodeficiency virus (HIV) or AIDS
- Previous treatment for testicular cancer
Not everyone with risk factors gets testicular cancer. However, if you have risk factors, it’s a good idea to discuss them with your doctor.
Research shows that many cancers can be prevented.
In rare cases, testicular cancer can be passed down from one generation to the next. Genetic counseling may be right for you. Visit our genetic testing page to learn more.