What is testicular cancer?

Testicular cancer is when cancer cells grow in the testicles, also called the testes. The testicles are the two male sex glands. They are located in the scrotum, the loose sac that hangs down beneath the penis. The testicles have two important functions: making sperm and making testosterone, a male hormone.

Testicular cancer is the most common type of cancer for men older than 15 years and younger than 35 years. Testicular cancer is very rare in children. About half of all testicular cancers are in men older than 20 years and younger than 35 years, but men of any age can develop it.

Most testicular cancers start in the germ cells of the testicles. These are the cells in the testicles that make sperm. There are two main types of testicular germ cells tumors: seminomas and non-seminomas. Seminomas grow and spread more slowly than non-seminomas. Testicular cancer can be in one or both of the testicles, but usually starts in just one. It is possible for testicular cancer to recur (come back) and affect the other testicle later.

Although there is no screening test for testicular cancer, men often have symptoms in the early stages and discover it early. Prognosis (outlook) depends on what type of tumor it is and how much it has spread, but many testicular cancers can be cured with the right treatment.


These are the symptoms of testicular cancer:

  • A lump in the testicle.
  • Swelling in the testicle. The testicle can become swollen for reasons besides cancer. It could be a hydrocele, which is fluid in the testes. Swelling can also be due to a varicocele. This is like getting a varicose vein in the testes.
  • Pain or heaviness in the scrotum.
  • Ache in the groin.

When to See a Doctor

See a doctor if you notice a lump or swelling in your testicles, or if you have any other symptoms of testicular cancer.

More Information

Risk Factors

Although researchers don’t know what causes testicular cancer, there are a few risk factors:

  • Having an undescended testicle. Before birth, the testicles develop in a boy’s abdomen and then descend (go down) into the scrotum. In many cases, the testicle descends on its own before the first birthday, but sometimes it doesn’t. Researchers don’t think that the undescended testicle causes cancer. Instead, it seems that something else might be causing both the cancer and the undescended testicle.
  • Abnormal development of the testicles.
  • Having testicular cancer in the past.
  • Family history of testicular cancer.
  • Being white. White men have a greater chance of getting testicular cancer than African American or Asian American men.

These risk factors increase a person’s chances of getting testicular cancer. But many men who get testicular cancer don’t have risk factors, and men with risk factors won’t necessarily develop testicular cancer.