What Are Prostate Cancer Risk Factors?
Reviewed by: HU Medical Review Board | Last reviewed: June 2019 | Last updated: April 2021
When talking about a condition, it is important to distinguish between its risk factors and its causes. Risk factors can be classified as modifiable or non-modifiable, and contribute to an increased risk of developing a condition. Modifiable risk factors are things we can potentially control or change, such as diet, obesity, or smoking. Non-modifiable risk factors are things we cannot change or were born with like race, family history, or age.
Who is at biggest risk for prostate cancer?
There are also special populations that may be at heightened risk for prostate cancer, or negative outcomes with prostate cancer. Three groups are African American men, gay men, and some veterans. Research has shown that these special populations have higher rates of prostate cancer or have delays in diagnosis and treatment compared to other social groups. These disparities are believed to be mainly based upon a combination social, environmental, and economic factors.
While risk factors increase a person’s risk of developing a condition, they are not the cause of the condition’s presence. For example, while exposure to environmental dangers like Agent Orange (a chemical used to destroy crops during the Vietnam War) can increase a person’s risk of developing prostate cancer, it itself does not cause prostate cancer. Being exposed to the chemical could lead to genetic mutations which can then go on to contribute to prostate cancer.
The cause of cancer lies in mutated genes that no longer function properly in the growth and development of cells. This leads to the uncontrolled cell growth and accumulation that contributes to tumor formation. Risk factors, including the ones listed below, can contribute to the potential mutation of critical cell lifecycle regulating genes, as well as increase the potential of possessing a hereditary mutation.
Factors out of our control
Non-modifiable risk factors are things we cannot readily change that could increase the chance of cancer developing within our cells. Examples of non-modifiable risk factors related to prostate cancer are:
- Age: Prostate cancer is very rare in young men, with the bulk of those diagnosed, around 71 percent, being between 55 and 74 years old. The average age at diagnosis has been reported as 66 years old.
- Race: Prostate cancer is more common in African American men than in any other male racial demographic. After African American males, the number of new cases each year is highest for white men, followed by Asian or Pacific Islander men, and American Indian or Alaskan Native men. Death due to prostate cancer is also highest for African American males.
- Ethnicity: Non-Hispanic men are nearly 1.3 times more likely than their Hispanic counterparts to develop prostate cancer.
- Genetics: Roughly 5-10 percent of prostate cancer cases are hereditary. Further, if a male has a close relative, such as a brother or a father, who has prostate cancer, it is estimated that he will have double the risk of developing the condition when compared to another male without an affected close relative. If a male has two or more close relatives with prostate cancer, this risk can increase five-fold. Certain mutated genes, including mutated BRCA1 and BRCA2 genes, can be inherited and increase the risk of developing prostate cancer later in life.
- Geography: It has been hypothesized that where a person is born and raised can affect their prostate cancer risk. For example, prostate cancer is the most common in North America and other developed areas such as Europe and Australia. This could be in part due to regions of genetic commonalities, or due to more frequent or intensive screening practices in developed nations.1-5
Modifiable risk factors
Modifiable risk factors are factors that could increase the chance of cancer developing, but that we may have the ability to change. Examples of modifiable risk factors related to prostate cancer are:
- Environmental exposures: Environmental factors and exposures such as exposure to Agent Orange (a chemical used to destroy crops during the Vietnam War), cigarette smoke, and radiation may increase the risk of developing prostate cancer.
- Diet: While this factor is still being researched further, evidence has been found that certain diets may contribute to an increased risk of prostate cancer. Elements of these increased risk diets include eating a high fat diet with lots of red meat and high fat-containing dairy products. Eating little to no fruits and vegetables has also been shown to possibly increase an individual’s prostate cancer risk.
- Obesity: This is another factor that is under further investigation, however, increasing evidence points toward obesity contributing to an increased risk of more aggressive types of prostate cancer.6,7
It is important to note that these are just examples of potential risk factors that have been studied and identified. Possessing any or all of these risk factors does not guarantee that an individual will develop the condition, but rather that their overall lifetime risk is higher than those without these specific factors. Further research is underway to shed further light on these links, as well as to investigate other potential risk factors, such as the presence of prostatitis or sexually transmitted infections, as well as having a vasectomy.