What are the risk factors for testicular cancer?

While we do not know the exact cause of most cases of testicular cancer, we do know some of the risk factors linked to testicular cancer.

A risk factor is something that affects a person's chance of getting a disease. Different cancers have different risk factors. Some risk factors, such as smoking, can be controlled. Others, like a person's age or race, can't be changed. But having a risk factor, or even several, does not mean that a person will get the disease. And not having any risk factors doesn't mean you won't get the disease.

Scientists have found a few risk factors that make a man more likely to get testicular cancer. Even if a man has one or more risk factors for this disease, there's no way to know for sure what part those factors played in causing the cancer. Also, most men with testicular cancer do not have any of the known risk factors. Research in this area is going on.

Risk factors for testicular cancer

Undescended testicle: One of the main risk factors for testicular cancer is a problem called cryptorchidism, or undescended testicle(s). Before birth, the testicles normally develop in the belly of the fetus and then move down (descend) into the scrotum before birth. But in about 3% of boys, the testicles do not move into the scrotum. Sometimes the testicle stays inside the belly. In other cases, the testicle starts to come down, but gets stuck in the groin.

Men who have had cryptorchidism are several times more likely to get testicular cancer than those who did not have the problem. The risk is higher for men with a testicle in the belly as opposed to one that has moved down at least part way. Among men with a history of this problem, most cancers start in the testicle that has not moved down. But about 1 out of 4 occurs in the normal testicle. Because of this, some doctors think that cryptorchidism is not the direct cause of testicular cancer. They believe that some other problem causes both the cancer risk and the cryptorchidism.

Most testicles will descend on their own in the child's first year. Sometimes surgery (called orchiopexy) is needed to bring the testicle down into the scrotum. Surgery done when a child is younger may be more likely to reduce the risk of testicular cancer than surgery done when the child is older, but the best time to do this surgery is not clear.

Family history: A family history of testicular cancer increases the risk. If a man has the disease, there is a higher risk that his brothers or sons may also get it. But very few cases of testicular cancer are actually found in families.

HIV infection: There is some evidence that men infected with HIV (human immunodeficiency virus) have an increased risk of testicular cancer. This may be especially true for men who have AIDS. No other infections have been shown to increase testicular cancer risk.

CIS (carcinoma in situ): CIS is described in "What is testicular cancer?” It isn't clear how often CIS in the testicles becomes cancer. It is sometimes found when a man is tested for infertility. It may also be found when a man has a testicle removed because of cryptorchidism. Radiation or surgery (to remove the testicle) is used to treat CIS. Since we don’t know how often CIS becomes true (invasive) cancer, it isn’t clear that treating CIS is a good idea. Some experts think that it may be better to wait and see if the disease gets worse or becomes a true cancer. This could allow many men with CIS to avoid the risks and side effects of treatment.

Cancer of the other testicle: Men who have been cured of cancer in one testicle have an increased risk (about a 3% to 4% chance) of getting cancer in the other testicle.

Age: About half of testicular cancers occur in men between the ages of 20 and 34. But this cancer can affect males of any age, including infants and older men

Race and ethnicity: White American men are about 5 times more likely to get testicular cancer than are African-American men. Whites have more than 3 times the risk of Asian-American and American Indian men. The risk for Hispanics falls between that of Asians and non-Hispanic whites. The reason for these differences is not known.

Body size: Some studies have that the risk of testicular cancer is somewhat higher in tall men but other studies have not shown a link.