The exact cause of testicular cancer is not known. Certain things called risk factors may increase the chance of developing it.

Undescended testicle (known as cryptorchidism)

If you had an undescended testicle as a child you have a higher chance of getting testicular cancer. The risk may be higher if you did not have surgery, which is usually done before the age of 2.

The testicles develop inside the tummy (abdomen) of an unborn baby. Usually, they drop down (descend) into the scrotum at birth, or within the first year. Sometimes this doesn’t happen so the child has surgery to bring the testicle into the scrotum.

Having surgery to bring down the testicle means you can regularly check your testicles and notice any changes early.

If you are worried about testicular cancer and would like to talk to someone, we're here. You can:

• Call the Macmillan Support Line on 0808 808 00 00.
• Chat to our specialists online.

Family History

You have a slightly higher risk of testicular cancer if you have a brother or father who has had testicular cancer. Researchers have found that this is partly due to changes in certain genes. Research continues to look at what genes may increase the risk.

Carcinoma in situ (CIS)

Carcinoma in situ (CIS) are abnormal cells in the testicle that can develop into testicular cancer if they are not removed.

CIS is sometimes found when you have a biopsy of the testicle. For example, you may have a biopsy to investigate infertility (being unable to have children).

Treatment for CIS may include:

• surveillance
• radiotherapy
• or surgery.

The treatment you may have depends on what certain blood tests show.

Cancer in the other testicle

A small number of people who have had treatment for testicular cancer will develop cancer in the other testicle.

It is important to know:

• how to check your testicles
• the symptoms of testicular cancer.

Talk with your GP if you are worried about testicular cancer coming back.

Ethnicity

Testicular cancer is more common in white men than in African‑Caribbean or Asian men.

Height

You may have a higher risk of testicular cancer if you are taller than average. Doctors are not sure why this is.

HIV

If you are HIV positive you have an increased risk of developing testicular cancer. There is an especially increased risk of a type of testicular cancer called seminoma.

Factors that do not increase testicular cancer risk

There is no evidence to suggest that injury to a testicle increases your risk of getting cancer. But an injury to a testicle or to the groin may bring a testicular cancer to your doctor’s attention.

Having a vasectomy does not increase the risk of getting testicular cancer.