Causes and risk factors of testicular cancer

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:

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:

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


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


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

Human immunodeficiency virus (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.

About our information

  • Reviewers

    This information has been written, revised and edited by Macmillan Cancer Support’s Cancer Information Development team. It has been reviewed by expert medical and health professionals and people living with cancer. It has been approved by Senior Medical Editor, Dr Jim Barber, Consultant Clinical Oncologist.

    Our cancer information has been awarded the PIF TICK. Created by the Patient Information Forum, this quality mark shows we meet PIF’s 10 criteria for trustworthy health information.

Content under review

Due to the pandemic, there have been delays in us updating this information as quickly as we would have wanted. Our team is working hard to put this right.

The language we use

We want everyone affected by cancer to feel our information is written for them.

We try to make sure our information is as clear as possible. We use plain English, avoid jargon, explain any medical words, use illustrations to explain text, and make sure important points are highlighted clearly.

We use gender-inclusive language and talk to our readers as ‘you’ so that everyone feels included. Where clinically necessary we use the terms ‘men’ and ‘women’ or ‘male’ and ‘female’. For example, we do so when talking about parts of the body or mentioning statistics or research about who is affected. Our aims are for our information to be as clear and relevant as possible for everyone.

You can read more about how we produce our information here.