PROSTATE CANCER AND THE ROLE OF BRCA
After lung cancer, prostate cancer is the second most common cancer diagnosis for men. According to the Canadian Cancer Society, prostate cancer accounts for one-fifth, or 20 percent, of all new cancer cases in men. On the other hand the five-year net survival rate is high for prostate cancer at 93 percent.
The Canadian Cancer Society attributes the declining mortality rate for prostate cancers to success in prevention, screening, and treatment. A key component to any prevention strategy is increased awareness and education about prostate cancer.
In Canada, one in nine men will be diagnosed with prostate cancer in their lifetime. When detected early, prostate cancer is one of the most successfully treated types of cancer, so it’s important to be aware of your risk factors and get checked. Screening for prostate cancer usually involves a blood test, called a prostate-specific antigen (PSA) test to measure PSA levels in the blood. It takes around 10 minutes, and would need to be ordered by your health care practitioner.
While high PSA levels could indicate prostate cancer, they could also be caused by other factors. Your doctor will likely discuss the risks and benefits of this test with you, as well as other potential risk factors for developing prostate cancer.
RISK FACTORS FOR PROSTATE CANCER
When it comes to developing any cancer, there are multiple risk factors that could lead to a diagnosis, including lifestyle, genetic, and environmental factors. However, these factors only increase your risk and don’t necessarily lead to cancer, and cancer can develop in people with no risk factors.
One of the strongest risk factors for prostate cancer is a family history of the disease, and the risk is higher if a first-degree relative (parent, sibling, or child) has been diagnosed with the disease. Another strong genetic risk factor for prostate cancer is a mutation in the breast cancer predisposition gene 2 (BRCA2). Some men might consider being tested for BRCA mutations under the following conditions:
- If there’s a history of prostate, breast, or ovarian cancer in the immediate family, particularly among younger members.
- If other family members test positive for BRCA1 or BRCA2 mutations.
- If they are of Ashkenazi Jewish descent, since BRCA mutations occur frequently in this ethnic population.
It’s important to note that BRCA gene changes aren't common and having a negative BRCA result does not guarantee that you will not develop cancer. Most provincial health plans will cover the cost of genetic testing if you meet certain conditions. Alberta Health Services recommends genetic counselling both before and after BRCA genetic testing to help understand the benefits, risks, and possible outcomes of the test.
Age is also a risk factor. The chance of being diagnosed with prostate cancer increases after age 50, and it’s diagnosed most often in men in their 60s.
WHAT HAPPENS IF PSA LEVELS ARE HIGH?
The prostate is a walnut-sized gland that sits underneath the bladder, near the rectum. It manufactures a specific protein, called prostate-specific antigen (PSA), which can be measured as an indicator of its health. If a PSA level is elevated, this could be a sign of prostate cancer.
Medical imaging can be ordered to assess the prostate, but traditionally a prostate biopsy is ordered to investigate high PSA levels and determine whether prostate cancer is present. During a standard transrectal prostate biopsy a needle is inserted into the prostate gland, and twelve random tissue samples are collected and sent to a lab for analysis.
Because prostate cancer is known to be multifocal in nature, random sampling has its challenges – prostate cancers can be omitted in the tissues samples. Both overestimation and underestimation of the grade and burden of prostate cancer is a concern. Prostate biopsy is also an invasive procedure – not without risk. Since 2012, improvements in magnetic resonance imaging (MRI) technology and increased research into the subject has lead to MRI being used more often to evaluate men suspected of having prostate cancer. The technique can help guide decisions about prostate biopsy.
Mayfair Diagnostics recently add a 3T magnet at their Mayfair Place location. This stronger magnet has the potential to generate more detailed or faster imaging. MRI is very good at examining soft tissues such as joints, muscles, tendons and ligaments, as well as small peripheral nerves. The highly sensitive diagnostic information that 3T imaging can provide for the prostate can be very helpful in determining the management of prostate-related disease.
The Prostate Imaging – Reporting and Data System (PI-RADS) was initiated in Europe in 2012. It outlined technical parameters for prostate MRI and helped guide specific sequences that would be useful for prostate imaging. This lead to a number of research projects around the world that looked at the usefulness of prostate MRI for prostate cancer, including several based at the Prostate Cancer Centre. In 2018, the New England Journal of Medicine published the results of the Precision Trial that affirmed that, “…in men with a clinical suspicion of prostate cancer, we found that a diagnostic pathway including risk assessment with MRI before biopsy and MRI-targeted biopsy in the presence of a lesion suggestive of cancer was superior to the diagnostic pathway of standard transrectal ultrasonography–guided biopsy.”
It’s important to discuss with your doctor your family history and other risk factors, the risks and benefits of screening tests and medical imaging, and any other questions or concerns about your health.
For more information about Mayfair Diagnostics, please visit our services page.
The American College of Radiology (2015) PI-RADS: Prostate Imaging – Reporting and Data System. www.acr.org. Accessed October 21, 2019.
Castro, E. and Eeles, R. “The role of BRCA1 and BRCA2 in prostate cancer.” Asian Journal of Andrology. 2012 May; 14(3): 409–414. Accessed October 9, 2020.
Government of Alberta (2019) “Prostate Cancer Screening: Should I Have a PSA Test?” www.myhealth.alberta.ca. Accessed October 9, 2020.
Kasivisvanathan, V., et al. (2018) “MRI-Targeted or Standard Biopsy for Prostate-Cancer Diagnosis.” The New England Journal of Medicine. 2018; 378:1767-1777. Accessed October 21, 2019.
Schmidt, C. (2019) “Researchers urge prostate cancer screening for men with BRCA gene defects.” Harvard Health Blog, www.health.harvard.edu. Accessed October 9, 2020.