Although there are many risk factors associated with prostate cancer, including age, race/ethnicity, genetic predisposition, obesity, and diet (to name a few), one particular risk factor that deserves additional attention is men with a family history of prostate cancer. Of all the major cancers, prostate cancer is one of the most likely to be inherited and this article will focus on the significance of family history when considering your risk of prostate cancer.
Why is a family history of prostate cancer important?
Your family history is information about health problems that have affected your family. Families have many common factors, such as their genes, environment, and lifestyle. Taken together, these factors can help suggest if you are more likely to get certain health conditions. Inside the DNA in each of the cells in our bodies are “instructions” called genes, which are passed down (i.e., inherited) from our parents. Genes control everything in the body, including how the body grows and works. If something goes wrong with genes, it can sometimes cause cancer. You may have an increased risk of getting a type of prostate cancer caused by genetic changes that are inherited if:
- You have more than one first-degree relative (father, son, or brother) who had prostate cancer, including relatives in three generations on your mother’s or father’s side of the family. This includes an approximately 2 to 3 times increased risk of getting prostate cancer if your father or brother had it, compared to a man with no relatives with prostate cancer.
- You were diagnosed with prostate cancer when you were 55 years old or younger
- You were diagnosed with prostate cancer, and other members of your family have been diagnosed with breast, ovarian, or pancreatic cancer
Among men with a family history of prostate cancer, a subset will have so-called “hereditary prostate cancer.” This means it is assumed that a specific gene is being passed down that causes the disease. To meet the criteria for this group, a family must have three affected generations, three first-degree relatives affected, or two relatives diagnosed prior to age 55. However, most men with a family history of prostate cancer will not fit these criteria. Nonetheless, family history remains an important predictor of a man’s risk of prostate cancer.
I have a family history of prostate cancer, so what does this mean?
- Impact on Outcomes: Although having a family history of prostate cancer increases your risk for prostate cancer, this has not been consistently shown to increase the risk of aggressive cancer. In a U.S. study of more than 37,000 men in the Health Professionals Follow-up Study, a family history of prostate cancer was associated with a 72% increased risk of lethal disease. Importantly, those with a family history of breast cancer also had a 34% increased risk of lethal prostate cancer. However, a study of 9,459 men from South Australia showed that men with a family history of prostate cancer had improved survival compared to men without a family history. These improved survival outcomes may be explained by starting PSA screening early among men with a positive family history.
- Impact on Screening: For most men, a family history of prostate cancer will not necessarily change prostate cancer screening recommendations and when to start screening. A man’s age, race, and overall health are also considered to decide if and when screening should start. However, screening is recommended earlier for a minority of men that have a known aggressive genetic risk for prostate cancer (with a mutation in genes called BRCA2 or HOXB13). International expert guidelines recommend that these men begin PSA screening at age 40, or 10 years before the youngest age at which prostate cancer was diagnosed in their family — whichever is earliest. These guidelines also recommend that screening begin at 45 years of age for men with BRCA1 Many studies have shown that men with these genetic mutations are diagnosed at an early age with aggressive, and often fatal, prostate cancer.
It is critical to understand your family history of not only prostate cancer, but other cancers such as breast, ovarian, and pancreatic cancer. The age at which your family members were diagnosed is also important to know. It’s equally important for your doctor to know this information, along with your age, race, and overall health. This way they can guide you on your overall risk for prostate cancer and when to start prostate cancer screening.