Prostate Cancer: Do I need genetic testing?
by Joy Larsen Haidle, MS, LGC
Joy Larsen Haidle, MS, LGC, is a past-president of the National Society of Genetic Counselors and a genetic counselor at the North Memorial Health Cancer Center in Minneapolis.
When Al Roker announced his prostate cancer diagnosis, he shared his desire to use his platform to educate others, presenting an ideal time to continue the conversation. Prostate cancer is common for men--1 in 9 will develop prostate cancer over their lifetime. However, those odds increase to roughly 1 in 7 for African American men. Many prostate cancers are slow growing and lead to a good prognosis, however, some prostate cancers are more aggressive and finding those cancers early becomes important to help those men do well too.
Prostate Cancer Screening Basics
Prostate specific antigen (PSA) testing and digital rectal exams (DRE) may help identify changes in the prostate suggestive of cancer. PSA has a normal range and it is often useful to look at the number as a quick guide to determine if further tests are needed. It is also important for men to note if the PSA level doubled from last year’s value to this year’s value, as that may also indicate a need for additional testing.
Men with a family history of prostate cancer often start prostate screening at the age of 45 years, however, African American men might be advised to start their screenings at age 40 due to the higher rate of prostate cancer and the tendency to be more aggressive. If there is an inherited risk in the family, surveillance is often tailored to the gene involved, but often starts at 40 years. Talk with your doctor about the best surveillance plan for you.
Diagnosing Prostate Cancer
When a biopsy or surgery is done, a Gleason score is assigned to the tumor. The Gleason score serves as an indicator as to how aggressive the tumor may be and can be found on the pathology report. Having a Gleason score of 7 or higher is indicative of an aggressive prostate cancer. Ask your doctor about your Gleason score as well as treatment decisions. As you share information with family members about the prostate cancer diagnosis, it is helpful for them to know the age at the time of diagnosis and it is also helpful for relatives to know the Gleason score.
Recent data suggests that the behavior of a prostate cancer may hint at the possibility that the cancer developed due to an inherited risk factor. Men whose prostate cancer has a Gleason score of 7 or higher or who have metastatic prostate cancer are candidates to consider genetic testing regardless of their age at the time of diagnosis or their family history as the result of the test may be used to help guide treatment decisions. Men who are young at the time of the diagnosis (60 years and under) or who are Ashkenazi Jewish and have prostate cancer are also candidates to consider genetic testing.
Men whose prostate cancer has a Gleason score of 6 or lower may still be candidates to consider genetic testing, especially if there is a family history of prostate cancer or a pattern of other cancers. It is always easier to spot a pattern in the family when multiple relatives have the same kind of cancer, but “other “ cancers may also be important to note too. In looking at a family history, the genes associated with prostate cancer risk may also be associated with risks for breast, ovarian, colon, pancreatic and/or male breast cancer. Talk with your family to determine if others have been diagnosed with cancer, the kind of cancer and their ages at the time of diagnosis. Ask if the women in the family had their ovaries and uterus removed, their age at the time of surgery and the reason. It is also helpful to learn if family members have had colon polyps, the number of polyps, ages and the kind of polyps. Genetic testing has become more common, so ask family members if they have already had genetic testing and if they would be willing to share results. Meeting with a genetic counselor can help determine if the cancers in the family are likely to have an inherited component and if you would be eligible for genetic testing.
A common misconception is that the person who was diagnosed with cancer does not need to pursue genetic testing and instead the healthy family members should do it to determine their cancer risk. In the ideal situation, the person with a cancer diagnosis is the best testing candidate to determine if the test can work and answer questions for their family. If the test does not identify an inherited risk in that person, then using that same test for healthy family members is often not worth it. The negative test result in that setting may provide false reassurance and may limit access to the appropriate screening. If however, an inherited risk is identified, then healthy family members have an accurate test to determine whether or not they are at increased risk to develop a cancer over their lifetime. However, not everyone wants to pursue genetic testing. So, if the ideal testing candidates are unwilling or unable to pursue testing then healthy family members are candidates to consider it as long as they understand the limitations in interpreting the results.
Genetic testing is complex and not all tests are equal. Often testing done through a direct to consumer laboratory such as 23andMe is not sufficient to identify an inherited cancer predisposition and anything identified through these kinds of laboratories should be confirmed through a medical laboratory. A genetic counselor can help determine which test is best for you and discuss how the result may be used to inform your medical decisions.
This holiday season, let’s utilize Mr. Roker’s mission for awareness and discuss these issues with our family members. Prostate cancer is important in evaluating family histories and men are an important part of these conversations. Knowing about an inherited risk is important to help make treatment decisions and may also help prevent cancer in family members. Genetic counselors are available for in-person appointments as well as over the telephone or telehealth visits. Visit www.Findageneticcounselor.com to connect with a genetic counselor near you.