The Prostate Cancer Genetic Risk Score
The prostate cancer genetic risk score provides an estimate of your lifetime risk, by age 85, of developing prostate cancer. This score is based on your ethnic background and genetic makeup. Knowing your risk of developing prostate cancer can help you make informed prevention management decisions such as earlier screening and treatment.
The scores are categorized in three buckets:
How can the results help me?
The Prostate Cancer GRS helps in calculating your lifetime risk of developing prostate cancer, by age 85. National society guidelines recommend discussion for prostate cancer screening only at age 55. If you are found to have an increased risk of developing prostate cancer based on your genetic markers, age, and ethnicity, you can talk to your physician about earlier and more frequent screening to help prevent and catch the disease early.
1in 7 men will develop prostate cancer in their lifetime. If caught early, the survival rate is near 100%.
1. SEER Stat Fact Sheets: Prostate Cancer. National Cancer Institute. (Accessed on 03/2019)
Background
Due to advances in medical science, connections have been established between one’s genetics (in DNA) and one’s likelihood of developing specific medical conditions, such as cancers.
DNA is made of billions of nucleotides, which are small molecules that bind together to form long strands. These long strands of DNA are called “chromosomes.” Chromosomes contain genes, which provide information that is necessary for human cells to function and sustain life. While the vast majority of nucleotides are the same for all humans, some differ. A portion of these individual differences in DNA called “single nucleotide polymorphisms” (SNPs) are associated with specific diseases. For example, there are ~100 known SNPs associated with prostate cancer; the more risk-associated differences one has in their DNA, the more likely they are to develop prostate cancer.
The Test
These SNPs may be additively combined to generate a Genetic Risk Score (GRS). The Genetic Risk Score, developed by NorthShore University HealthSystem, aims to assess individuals’ risk of developing prostate cancer compared to men in the general population. The test looks at individuals’ DNA and allows scientists to generate a GRS value that describes one’s risk for developing various diseases, in this case, prostate cancer.
This genetic test differs from other genetic tests in that it does not assess the presence or absence of harmful genetic variants, which are genetic changes in which one change can have a large impact in developing prostate cancer (e.g. BRCA1 and BRCA2). Instead, the test uses SNPs, which have a small individual impact, but a larger cumulative impact (closer to that of having a genetic mutation).
A personalized GRS for cancer is a number that tells whether an individual is more or less likely to develop a particular type of cancer over his or her lifetime as compared to the average person. With this genetic risk score, you will be presented with personalized guidelines for cancer screening tests based on your age, race, family history of cancer, and your genetic risk score. You are encouraged to discuss these results with a primary care physician and to make an appointment to further discuss these findings with a genetics counselor (at no additional charge) for further guidance if still concerned.