Prostate Cancer: Know Your Risk Factors

It's important to understand the meaning of "risk factor." Healthcare providers look at risk factors to gauge the relative likelihood a person will develop a certain disease.

Risk factors are based on population data analyzed to identify specific criteria that prostate cancer patients, for example, have in common. These criteria can include genetic, individual and environmental factors, among others.

Risk factors are all about odds and chances, not certainties. It's important to understand that even if you have risk factors for prostate cancer, there's no guarantee you'll get it.

By the same token, even if you don't have major risk factors, you may still develop prostate cancer.

With that caveat, let's dive in.

Nearly every conversation about prostate cancer includes age, because it's almost exclusively a disease that strikes older men.

In fact, prostate cancer is so rare in men younger than 40, it is virtually nonexistent, according to Johns Hopkins Medicine. The American Urological Association (AUA) guidelines recommend men younger than 40 not be screened at all.

Around age 50, the odds of contracting prostate cancer start to rise sharply. Men older than 65 are diagnosed with 60 percent of all prostate cancers, according to the ACS.

We'll get into more detail about screening in a future installment of this series. But the AUA basics for prostate-specific antigen (PSA) screening by age are:

• 40 and younger: No screening recommended.
• 40 to 54 with average risk: No routine screening recommended.
• 55 and younger with higher risk: Screening should be discussed with a healthcare provider.
• 55 to 69: This age group shows the greatest benefit of screening.
• 70 and older or men with less than a 10- to 15-year expected life span: No routine screening recommended.

After age, family history is the next aspect doctors evaluate when discussing a man's potential for developing prostate cancer.

"There's a strong hereditary component to prostate cancer, so family history plays a big role," said Neel Parekh, M.D., a urologist and fertility specialist affiliated with the Cleveland Clinic. "Actually, if your brother, followed by your father, has had prostate cancer, those are probably the two biggest risk factors."

Having either a father or a brother with prostate cancer more than doubles your risk of developing it, according to the ACS. And if you have more than one first-degree relative (father, brother or son), including relatives in three successive generations on either your mother's or father's side, who has had prostate cancer, the risk is much higher, as well, according to the Centers for Disease Control and Prevention (CDC).

As you comb through your family tree looking for prostate cancer, it's important to note the age at which a first-degree relative developed the disease. If they were diagnosed with prostate cancer relatively young—age 55 or younger—that increases your risk, too.

One more wrinkle to the family tree factor: If you have a family history of prostate cancer plus other types of cancer—especially ovarian, pancreatic or breast—that, too, places you at higher risk, according to the National Cancer Institute (NCI).

"Prostate cancer tends to run in families. But certainly, if you don't have a family history, it doesn't mean you're free and clear," Heppe said. "If you do have a family history, you ought to get checked once a year starting at age 40."

The third leg of the triad of most-watched prostate cancer risk factors is race and ethnicity.

It's long been known that men of African descent have a dramatically higher chance of developing prostate cancer than men of other racial and ethnic backgrounds. The disparities are striking:

• African American men face 76 percent more risk of getting prostate cancer than white men.
• African American men are more than twice as likely to die if they contract prostate cancer than white men.
• Even low-grade types of prostate cancer are likely to be more aggressive for African American men.

Here's the incidence rate for men of different backgrounds, according to a CDC analysis covering prostate cancer from 2003–2017:

• African American: 202 per 100,000
• White non-Hispanic: 122 per 100,000
• Hispanic: 106 per 100,000
• Asian/Pacific Islander: 67 per 100,000

However, modern research on genetics, race and oncology is helping to improve the odds for Black men. One standout prostate cancer study published in January 2021 in the journal Nature Genetics took data from nearly a quarter-million men of African, Asian, European and Hispanic heritage across five continents.

"There's very strong evidence that genetics plays an important role [in prostate cancer]," said study lead Chris Haiman, Sc.D., a professor of preventive medicine who heads up the cancer epidemiology program at the University of Southern California. "Through this study, we identified close to 300 markers that are common in the population that can really help identify men who are at high risk and men who are at low risk of developing prostate cancer."

While the evidence for some prostate cancer risk factors is more or less indisputable, research into other factors presents a less clear picture.

Some studies have linked a high-fat diet to prostate cancer, with researchers suggesting that an anti-obesity drug could be used to combat metastatic prostate cancer. Other studies have shown that obese men who contract prostate cancer tend to have worse outcomes, a higher rate of mortality and more aggressive forms of the disease.

While more work needs to be done to prove a definitive link, there are other reasons to believe a high-fat, meat-heavy diet may be a factor in prostate cancer's development.

"There seems to be increased risk with our Western diet," Heppe said. "People in Asia have much less risk of prostate cancer than people living in the U.S. But if somebody from Asia moves to the U.S., within one generation, their risk is the same, so we think it's dietary-related. Being overweight seems to put you at risk, as well."

Some studies suggest that exposure to certain chemicals, such as bisphenol A, may contribute to prostate cancer incidence. Others show a link to lead exposure, and still others show a possible occupational link for forestry workers, police officers and white-collar employees, among others.

However, all of these studies are very limited and require further research before they're deemed conclusive.

Armed with knowledge about the risk factors of prostate cancer, you can take a great deal of control. If you have concerns about any of these risk factors, speak with your doctor about the testing regimen that is appropriate for your age and background.

The modern science around prostate cancer detection and treatment has advanced by leaps and bounds in recent years, as we'll see in subsequent installments in this series. But unless you open the door to getting diagnosed in the first place, all the tech in the world can't help.