A risk factor is anything that increases your chances of getting a disease like cancer. Different cancers have different risk factors. Some cancer risk factors, like smoking, can be changed. Others, like a person’s age or family history, can’t be changed.
But having a risk factor, or even many, doesn’t mean that you will get the disease. And some men who develop penile cancer might have few or no known risk factors.
Human papillomavirus (HPV) infection
HPVs are a group of more than 200 related viruses. They are called papillomaviruses because some of them cause growths called papillomas (more commonly called warts).
Certain “high-risk” HPV types have been linked with certain cancers. Infection with these types of HPV appears to be an important risk factor for penile cancer.
Other HPV types can cause different types of warts in various parts of the body. Certain HPV types can infect the genital organs and the anal area, causing raised, bumpy warts called condyloma acuminata (or just condylomas).
While the types of HPV that cause genital warts are different from the HPV types linked with penile cancer, men who’ve had genital warts have a higher risk of penile cancer. This might be because of lifestyle factors or behaviors that make them more likely to get multiple types of HPV.
HPV infection is common. In most people, the body clears the infection on its own. But in some people, the infection doesn’t go away. Long-term infection, especially with certain HPV types, can cause some types of cancer, including penile cancer. Men who are not circumcised may be more likely to get and stay infected with HPV.
How HPV spreads
HPV is passed from one person to another during skin-to-skin contact with an infected area of the body. HPV can be spread during sexual activity, including vaginal, anal, and oral sex, but sex doesn’t have to occur for the infection to spread. All that’s needed is skin-to-skin contact with an area of the body infected with HPV.
Anyone who has sexual activity with another person can be at risk for HPV if their partner has been exposed to HPV. At the same time, HPV infections are more common in people who have had many sex partners.
Infection with HPV can also spread from one part of the body to another. For example, infection may start in the penis and then spread to the anus.
To learn more, see our HPV section.
Not being circumcised
Circumcision removes all (or part) of the foreskin. This procedure is most often done in infants, but it can be done later in life, too.
Men who were circumcised as children have a lower chance of getting penile cancer than those who were not. The same protective effect is not seen if circumcision is done as an adult.
The reason for the lower risk in circumcised men is not entirely clear, but it may be related to other known risk factors. For example, men who are circumcised can’t develop the condition called phimosis (see below). Men with phimosis have an increased risk of penile cancer.
In weighing the risks and benefits of circumcision, doctors consider the fact that penile cancer is very uncommon in the United States, even in uncircumcised men.
Although the American Academy of Pediatrics has stated that the health benefits of circumcision in newborn males outweigh the risks, it also states these benefits are not great enough to recommend that all newborns be routinely circumcised. In the end, decisions about circumcision are highly personal and often depend more on social and religious preferences than on medical evidence.
Phimosis
In those who are uncircumcised, the foreskin can sometimes become tight and difficult to retract over the glans. This is known as phimosis.
Penile cancer is more common in those with phimosis. The reason for this is not clear, but it might be related to the build-up of smegma (a cheese-like substance under the foreskin) or from inflammation that results from phimosis. Good genital hygiene is very important. Those who are uncircumcised need to pull back (retract) the foreskin and clean the entire penis.
Smoking and other tobacco use
Men who smoke or use other forms of tobacco are more likely to develop penile cancer.
Tobacco use exposes your body to many cancer-causing chemicals. These harmful substances are absorbed into the blood, where they can travel throughout the body to increase the risk of cancer in many different areas. Researchers believe that these substances damage genes in cells of the penis, which can lead to penile cancer.
UV light treatment of psoriasis
Men who have a skin disease called psoriasis are sometimes treated with drugs called psoralens and then an ultraviolet A (UVA) light source. This is called PUVA therapy.
Men who have had this treatment have been found to have a higher rate of penile cancer.
Older age
The risk of penile cancer goes up with age. In the US, the average age of a man when he is diagnosed is about 60.
Human immunodeficiency virus (HIV) infection
Men living with HIV, the virus that causes AIDS, have a higher risk of penile cancer.
This might be linked to having a weakened immune system from the infection itself in some men. But it might also be linked to other risk factors that men with HIV are more likely to have. For example, men with HIV are more likely to smoke and to be infected with HPV.