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Prostate cancer family history — The Ultimate Guide

September 4, 2021

A prostate cancer family history is an important risk factor in determining someone’s risk of developing the disease. Having a family history of prostate cancer can increase men’s chance of developing prostate cancer to at least a 1 in 3 chance.  However, most people underestimate the impact and role of family history when managing their own risk .

In this guide, we will present all the facts on a prostate cancer family history. We have scoured the literature and consulted with some of the leading experts in the field to bring you all the answers. In this guide, we answer the following questions.

1.What is a family history of cancer?

2.What is the chance of developing prostate cancer with a family history?

3.How do you determine if you have a family history of prostate cancer?

4.What to do if you do have a family history of prostate cancer?

It is important to note that the information given in this article should not be used or relied upon as a substitute for a doctor’s advice and instructions. If you are looking to discuss your situation with a doctor who specialises in managing prostate cancer, our clinicians are ready to help. You can request a tele-consult with our clinicians by creating a secure account or by filling out our contact form.

1. What is a family history of cancer?

A strong link exists between family members having cancers. Individuals whose relatives have been diagnosed with cancer have an increased chance of developing the same cancer or other cancer types with similar profiles.

This is because of both genetics passed down through families and also common risk factors (for example, a family that is regularly in the sun together). If a family member is diagnosed with a cancer, this means the other families are now at an increased chance of developing this cancer.

From a medical perspective, a family history of cancer exists if one of your family members has been diagnosed with that cancer. However, it is crucial to know which person had cancer in your family. Not all family members influence your chance of developing cancer equally.

Which relatives should you consider for family history?

Two types of relatives – first-degree and second-degree relatives – are considered important in the cancer risk equation. The definition of these family members is as follows:


  1. First-degree relatives are your closest biological relatives — siblings, mother, father, and children. There is a 50% chance you share the same genetics as your first-degree relatives.
  2. Second-degree relatives are your broader biological family — aunts, uncles, and grandparents. There is a 25% chance you share the same genetics as your second-degree relatives.

Because there is a high level of genetic similarity among first-degree relatives, they are the most important to consider when evaluating your risk of developing cancer. The risk from second-degree relatives is important, though not as significant as that of first-degree relatives.

Beyond the first and second-degree relatives, the influence is too small to show any immediate impact on risk. A cousin, for example, does not significantly affect your risk as there is only a 12.5% chance you share the same genetic makeup.

It is important to emphasise that these are your biological (or blood) relatives. Your partner or adopted family do not contribute to your risk of developing cancer, even if they may have a history of cancer.

It is also important to remember that certain cancers only affect certain genders. For example, prostate cancer only affects those who are anatomically male as they have a prostate. The good news, it is hard to have an increased risk of prostate cancer without a prostate.

How does a family history cause cancer?

As we have mentioned previously, a strong link exists between family members having cancers. There are two reasons why cancer runs in families:

  1. Similar lifestyles and habits: Most families have similar lifestyles and habits, which can expose the entire family to the same risk factors such as sunlight, smoking, drinking and diet. All these factors increase someone’s risk of developing certain cancers. This type of family history is complicated to quantify and not used as much.
  2. Inherited Genetic Risk: Genetics also play a crucial role in predicting the risk of cancer. Families pass on genes, and some of these genes contain the code for a higher risk of developing certain cancers. The BRCA genes for example, are the genes that increase breast cancer risk (BRCA is an abbreviation for BReast CAncer).

When doctors ask you about your family history of cancer, they are attempting to determine whether you have a higher risk due to inherited reasons. From this information, they can better predict your risk of developing cancer. Prostate cancer is a highly heritable cancer; the next section goes into further detail on that.

Is prostate cancer genetically inherited?

Prostate cancer is one of the most heritable cancers. Your risk of developing prostate cancer is higher if a family member has been diagnosed with prostate cancer.

The heritable risk for prostate cancer, and most cancers in general, goes beyond just those family members who had prostate cancer. For instance, you can inherit your prostate cancer risk from female family members with breast cancer (Barber et al. 2018.)

Research has established the link between the BRCA gene (pronounced braca ) and the increased chance of developing prostate cancer. Men who carry the BRCA 2 gene have an increased lifetime risk of developing prostate cancer (Hemminki et al. 2010.)

A genetic test is required to confirm the presence of the BRCA genes. However, a family history of breast or ovarian cancer is an indicator that family members could carry the BRCA genes. For example, a family history of breast cancer could mean you inherited the BRCA 2 gene and thus have an increased risk of developing prostate cancer.

Importantly, the BRCA genes can be inherited from both sides of the family. Men are carriers of the altered gene, so you may have inherited the gene from your father.

The seriousness of this risk is well understood. Recent updates to the Prostate MRI Medicare Rebate in Australia subsidise men with a suspected BRCA gene due to assumed increased risk.

The lesson from this is to understand your family’s complete history on both sides of the family.

2. What is the chance of developing prostate cancer with a family history?

Now that we understand what a family history of prostate cancer is, we can explore to how much it changes your risk of developing prostate cancer.

There are two implications of a family history of prostate cancer. The first is that the chance of diagnosis with prostate cancer increases. The second is that if you have a prostate cancer family history, the risk of death also increases if diagnosed late.

When considering the increase in risk, several factors are required. These including the age of diagnosis of your family members and whether the family member perished from the disease. Generally, the younger the age of diagnosis and the more aggressive cancer, the higher the risk for you.

Consider the following scenarios.

One first-degree relative diagnosed with prostate cancer

The increase in risk due to a family history of prostate cancer is significant. Suppose your first-degree relative developed prostate cancer over the age of 55. In that case, studies suggest that your risk is between ~1.6x and ~1.8x that of a man with no family history.

On the other hand, if your first-degree relative developed prostate cancer younger than 55, that risk jumps to ~2.5x. As can be seen here, the age of diagnosis is also an important factor to consider when predicting risk of prostate cancer from family history.

Two or more first-degree relatives diagnosed with prostate cancer

Suppose two or more of your first-degree relatives developed prostate cancer when they were older than 55. In that case, you have a 3.5x risk of prostate cancer compared to a man with no family history.

If they developed prostate cancer younger than 55 that risk jumps to 6x that of a man with no family history.

For further reading on this, you can refer to the following sources below in the reference list. Chen et al. 2008, Grill et al. 2015, Klein et al. 1998,  Spain et al. 2008.

Second-degree relatives diagnosed with prostate cancer.

The link between first and second-degree relatives and prostate cancer is less established in the literature. However, the available data suggests that a second-degree relative will increase your risk by about 1.5x (Bruner et al. 2003). Other studies have shown that 3 or more second-degree relatives with prostate cancer can double your risk. If 5 or more second-degree relatives with prostate cancer may triple your risk (Schmidt.)

First-degree relatives diagnosed with breast cancer

While not as strong as first-degree relatives diagnosed with prostate cancer, the risk of prostate cancer increases in the presence of first-degree relatives with breast cancer. The increase in risk for prostate cancer in families with a history of breast cancer is ~1.2x when one first-degree relative was diagnosed with breast cancer and ~1.6 when two relatives were diagnosed. (Hemminki et al. 2010)

Examples of different prostate cancer family history types

To help with this, we’ve laid out a few different scenarios that may help you understand what your risk could be.

Is there an increased chance of death with a family history of prostate cancer?

Correct testing is required to ensure there is not an increased chance of death. Men have a higher likelihood of death if they have a family history of prostate cancer and inadequate testing (Abdel-Rahman 2019.) However, there is no increased risk of mortality if they have a family history with correct testing. Accurate testing allows for early detection and better treatment options. This highlights the need for men with a family history to test properly.

Did you need to determine if you are at a high-risk of developing prostate cancer?

Take our prostate cancer risk assessment.

3. How do you determine if you have a family history of prostate cancer?

The best way to determine your prostate cancer risk and whether you have a family history is through our free prostate cancer risk assessment. It takes you through all the essential questions that will appropriately categorise and classify your risk. However, if you are starting from the beginning and need to know who to ask and what to ask. Follow these steps.

Step 1 – Which family members should you ask about your family history of cancer?

The first people to ask are your first-degree biological relatives – your mother, father, siblings and children. The second people to ask are your second-degree biological relatives – your aunts, uncles and grandparents.

Step 2 – What should you ask about your family history of cancer?

This is a good opportunity to know about their entire history, but for cancers, you want to know:

This is also the time to be open about your personal medical history and an opportunity to discuss other conditions outside of family history.

Step 3 – What do you do with your family history of cancer information?

Communicate this with all your health professionals, your GP and your specialists— no need to worry if you are a Maxwell Plus patient. We prompt you for all this information. This information is essential as it informs the management plan that your healthcare providers will initiate for you.

Importantly

Do not assume that “not hearing/not knowing” is the same as not having a family history.

Many men believe they do not have a family history because they never heard about it from their relatives. When we surveyed our thousands of patients, ~60% do not have a family history. But when we asked how they know they do not have a family history, nearly 30% assumed no because they “had not heard”.

By now, we hope you understand the importance of family history, and this is something you need to be sure about.

What if I do not know my family history of cancer?

If you cannot determine your family history of cancer from your biological relatives, it is essential to notify your doctor about this detail. At Maxwell Plus, we consider both a scenario for the patient where they have a family history and do not.

Using this conservative approach allows our clinicians and our AI to decide whether further testing should happen. Our clinicians will then discuss both scenarios with the patient and most likely recommend they get a simple additional blood test to confirm their findings.

4. What do you do if you have a family history of prostate cancer?

There are three things to do if you have a family history of prostate cancer.

  1. Get tested at 40 years of age and continue getting tested each year.
  2. Get tested with a doctor that understands prostate cancer.
  3. Make sure your other male relatives are also getting tested.

When should men with a family history of prostate cancer get tested?

At Maxwell Plus, we recommend men with a family history of prostate cancer to get tested at 40 years old. From the initial test, we recommend a PSA test each year. The accepted age to stop testing is 70. However, we usually have a discussion with the patient to determine their health, fitness and broader lifestyle situation to decide whether or not they should continue getting tested.

If you have symptoms of prostate cancer or strong family history (2 or more first-degree relatives diagnosed), we recommend you discuss your situation with a Urologist even before you are 40 years old. Our Maxwell Plus Urologists are always ready and available to help.

How should men with a family history of prostate cancer get tested?

We recommend yearly PSA testing from the age of 40 onwards for men with a family history of prostate cancer. A more advanced blood test such as a PSA and Free-To-Total Ratio or Prostate Health Index may be an appropriate test depending on the individual’s risk. We also recommend a DRE (digital rectal exam) completed by a highly trained and competent Urologist.

More importantly, we recommend finding a doctor that understands your increased risk and the nuances associated with a family history so that these more advanced tests can be ordered and interpreted correctly. Maxwell Plus is the most accessible experts, being a telehealth company.


How can I encourage my brothers, cousins, and friends to get tested for prostate cancer?

It is essential to ensure your male family members are getting tested for two reasons.

  1. For their health. Early detection gives them the best chance of survival.
  2. For complete knowledge of your risk. If a brother is diagnosed with prostate cancer, this changes your risk. With such a diagnosis, your risk increases drastically from 2.0x to 5.0x the average.

Please encourage them to seek professional advice. Maxwell Plus is available to help them. We handle all reminders, and we will even co-sponsor their testing if they cannot afford the service. If you would like to refer your family members to us you can read this article on how to refer your friends and family to Maxwell Plus.

Summary — Prostate cancer family history

There are three important things to remember about prostate cancer and family history.

  1. A family history of prostate cancer is a significant predictor of your overall risk of developing prostate cancer. A family history of prostate cancer can increase your risk by up to 5.0x compared to the population average.
  2. First-degree relatives are most important when determining your prostate cancer family history. Second-degree relatives are also important but do not significantly influence your risk as first-degree relatives.
  3. If you have a family history of prostate cancer, you should be tested from 40 years old and continue to get tested each year. It is essential to find a doctor who understands prostate cancer.