Risk factors for testicular cancer
A risk factor is something that increases the risk of developing cancer. It could be a behaviour, substance or condition. Most cancers are the result of many risk factors. But sometimes testicular cancer develops in men who don’t have any of the risk factors described below.
Experts aren’t sure why, but the number of new testicular cancer cases diagnosed each year (called incidence) has steadily increased over the last several decades. Testicular cancer is the most common cancer in men 15–29 years of age. The number of men diagnosed with testicular cancer is low before puberty, increases significantly after age 14, peaks around age 30 and then declines by age 60.
Testicular cancer is more common in Caucasian men than in men of African or Asian ancestry. It occurs most often in men with a higher socio-economic status.
The following are risk factors for testicular cancer. Most of the known and possible risk factors are not modifiable. This means that you can’t change them. Until we learn more about these risk factors, there are no specific ways you can reduce your risk.
Risk factors are generally listed in order from most to least important. But in most cases, it is impossible to rank them with absolute certainty.
|Known risk factors||Possible risk factors|
Researchers have looked into vasectomy, injury to the testicles, tobacco, alcohol and diet. They have found that there is no link between these factors and a higher risk for testicular cancer.
Known risk factors
There is convincing evidence that the following factors increase your risk for testicular cancer.
Men who had an undescended testicle (called cryptorchidism) have a higher risk for testicular cancer. While a boy is in the womb, the testicles form in his abdomen. Normally they move down, or descend, into the scrotum before birth. Sometimes this doesn’t happen and one or both testicles don’t descend. Experts don’t know exactly what causes this abnormality. Sometimes the testicle will move down on its own (usually during the first year of the boy’s life). If this doesn’t happen, a surgeon will do an operation to move the testicle into the scrotum (called an orchiopexy).
If your father or brother had testicular cancer, you have a higher risk of developing it. Research is trying to find which genes may play a role in a family history of testicular cancer.
If you had cancer in one testicle, you have a higher risk of developing cancer in the other testicle.
Calcium deposits in the testicle (called testicular microlithiasis) increase a man’s risk of developing cancer. They are usually found when an ultrasound is done for other reasons.
Several studies show that being tall is a risk factor for testicular cancer. Researchers think this increased risk may be due to the effect of growth and puberty hormones.
The following factors have been linked with testicular cancer, but there is not enough evidence to show they are known risk factors. More research is needed to clarify the role of these factors for testicular cancer.
Men who have difficulty fathering children have a higher risk for testicular cancer. It is not clear if the fertility problems themselves cause testicular cancer or if whatever causes the fertility problems also causes testicular cancer.
If you start puberty earlier than normal, you are exposed to hormones for a longer period of time. This exposure may increase the risk of developing testicular cancer. Some studies show a link between early puberty and testicular cancer, but others don’t. Some studies suggest that starting puberty later than normal may reduce the risk.
Some studies show that men who are exposed to certain pesticides, such as organochlorine pesticides, may have a higher risk for testicular cancer. Other studies don’t show this link.
Some research shows that men with a weakened immune system due to HIV infection or AIDS (acquired immune deficiency syndrome caused by HIV infection) have a slightly higher risk of developing testicular cancer.
Some studies show that men who often smoke cannabis (marijuana) have a slightly higher risk for testicular cancer.
Diethylstilboestrol (DES) is a form of estrogen. Between 1940 and 1971, it was used to treat women who had certain problems with their pregnancies, such as miscarriages. Some studies suggest that men whose mothers who took DES have a higher risk of developing testicular cancer. Studies also suggest that being exposed to high levels of certain hormones during pregnancy may increase a man’s risk for testicular cancer.
Several studies have found that men who work as firefighters have a higher risk for testicular cancer.
Klinefelter syndrome is a rare genetic condition in which men have at least one extra X chromosome. It affects a man’s sexual development and can cause undescended testicles. Having undescended testicles increases the risk of developing testicular cancer, but it isn’t clear if this higher risk is directly related to Klinefelter syndrome.
Some studies show that N,N-dimethylformamide may increase the risk for testicular cancer. Men who work in fighter aircraft repair and acrylic or synthetic leather fibre manufacturing may come into contact with N,N-dimethylformamide.
Some studies show a link between dichlorodiphenyltrichloroethane (DDT) and testicular cancer. DDT is a pesticide that was banned in Canada in 1972.
Unknown risk factors
It isn’t known whether or not the following factors are linked with testicular cancer. It may be that researchers can’t show a definite link or that studies have had different results. More research is needed to see if the following are risk factors for testicular cancer:
- having a birth weight that is higher or lower than normal
- being infected with the Epstein Barr virus (EBV)
- working at certain jobs, including construction workers, concrete workers and printers
- working in certain industries, including paper, plastic and metal manufacturing
- being exposed to certain chemicals, including polychlorinated biphenyls (PCBs), flame retardants, phthalates and dioxin
Questions to ask your healthcare team
To make the decisions that are right for you, ask your healthcare team questions about risks.
The pouch of skin below the penis that contains the testicles.
I’m extremely grateful to the Canadian Cancer Society for funding my research with an Innovation Grant.
Great progress has been made
Some cancers, such as thyroid and testicular, have survival rates of over 90%. Other cancers, such as pancreatic, brain and esophageal, continue to have very low survival rates.