What are the risk factors for prostate cancer?

Prostate cancer affects about 13 out of every 100 American men, and 2–3 of these men will die from prostate cancer. So there is a high chance that you know someone who has been affected. Maybe it was someone close to you or maybe you’re concerned about your own risk. There are many different factors that contribute to an increased risk of prostate cancer, some of which cannot be changed (e.g., age), while other factors can be changed (e.g., smoking).

What is prostate cancer?
Prostate cancer occurs when malignant cells start growing out of control in the prostate, a small gland that helps make semen. Prostate cancer can cause a range of symptoms, including difficulty urinating, frequent urination, painful urination and ejaculation, blood in the urine or semen, and pain in the back, hips, or pelvis (1). However, it is important to note that these symptoms can also be caused by other issues, such as benign prostatic hyperplasia and bacterial prostatitis. For more information about other possible causes of an enlarged prostate, see our previous article here.

What are the known risk factors for prostate cancer?

• Age is the most common risk factor for prostate cancer, with the chance of prostate cancer rising rapidly after 50 years of age. In fact, about 60% of prostate cancers are found in men over 60 years (2).
• Race/ethnicity affects the risk of prostate cancer. In America, prostate cancer is more common in African American men and in Caribbean men of African ancestry. In addition, it tends to appear at a younger age in these ethnicities. It is currently unknown why these risk differences are present (2).
• Where you live in the world also affects your risk, as prostate cancer is more common in North America, northwestern Europe, Australia, and on Caribbean islands. Again, the reasons for this increased risk are not clear, although lifestyle factors (e.g., diet) are thought to play a role (2).
• Genetic factors are associated with an increased risk, such as inherited variants in the BRCA1 and BRCA2 genes (which are more commonly known to increase the risk of breast cancer) (2).
• A family history of prostate cancer (e.g., affected brother or father) can more than double the risk, suggesting other inherited genetic factors play a role (2).

What other possible risk factors for prostate cancer are there?

• Dietary differences may play a role, as there appears to be a slightly higher risk in men who eat a lot of dairy products (2).
• Obesity may play a role, but studies have come to differing conclusions on the impact of body weight for the risk or prostate cancer (2).
• Smoking has been shown in some studies to influence the risk of prostate cancer, but other studies did not reach the same conclusions. However, there is increasing evidence that smoking can increase the risk of dying from prostate cancer (2).
• Chemical exposures may increase the risk of prostate cancer. However, further research is required to confirm these associations (2).
• Having a vasectomy may slightly increase the risk, but further research is required to confirm this (2).

What are ways to reduce the risk of prostate cancer?
Unfortunately, many of the risk factors for prostate cancer cannot be changed, and further research is required to confirm the risks associated with the modifiable risk factors. However, routine screening is still the most effective way to reduce the chance of serious or fatal complications from prostate cancer, especially because early prostate cancer (when it is easier to treat) doesn’t usually cause any symptoms (3).

Screening for prostate cancer may include a prostate specific antigen (PSA) test, such as the one offered here. Elevated PSA can be indicative of prostate cancer, but may also occur due to benign (non-cancerous) conditions. More info about PSA is available here.

Another screening option is a digital rectal examination (DRE) when a health care provider inserts a gloved, lubricated finger into the rectum to feel the prostate. However, this is not recommended as an initial screening method by the US Preventive Services Task Force (1).

If the PSA test and/or DRE are indicating prostate abnormalities, additional diagnostic tests can be conducted, including an ultrasound and a prostate biopsy. The biopsy involves the removal of prostate tissue for examination under a microscope to detect cancer cells (1).

How is prostate cancer treated?
Treatment options for prostate cancer vary depending on the cancer stage and if it has spread elsewhere in the body. If it is determined that the cancer is unlikely to grow quickly and there are no symptoms, no treatment may occur. Instead, the affected person is closely monitored with more frequent PSA tests and prostate biopsies (1).

Other treatment options include surgery to remove the prostate (as well as surrounding tissues if necessary) and radiation therapy to kill the cancer cells. There are also several treatment options currently undergoing investigation, including cryotherapy, chemotherapy, high-intensity focused ultrasound, and hormone therapy (1).

References:
1. Prostate Cancer, Basic Information. (Reviewed August 2021). CDC.
2. Prostate Cancer Risk Factors. (Revised June 2020). American Cancer Society.
3. What is Prostate Cancer? (Revised August 2019). American Cancer Society.