In today’s society, most individuals have been touched in some way by cancer – whether personally, through a family member, friend or acquaintance. Cancer is a widespread group of diseases that affect millions of people in the United States and worldwide. It originates as an abnormal mutation to a person’s genes that causes them to divide and grow erratically. At the Austin Center for Radiation Oncology, the main focus of our practice is treating men with prostate cancer. We are also interested in hereditary cancers and genetic testing in relationship to prostate cancer.
Understanding genetic mutations
Cancer-causing gene mutations are categorized as being either an acquired mutation or a germline mutation.
Acquired mutations, also known as sporadic or somatic mutations, are the most common cause of cancer. These types of mutations develop when genes are damaged over a period of time. Typically, this damage occurs due to certain exposures, behaviors, or by advanced age. This type of genetic mutation can be influenced by tobacco use, ultraviolet rays, radiation exposure, poor dietary choices, physical inactivity, obesity or viruses.
Germline mutations, also known as inherited mutations, are far less common. An inherited gene mutation is passed onto a child from the DNA of either the father’s sperm or the mother’s egg. As the fertilized egg (zygote) begins to divide, the inherited mutation becomes part of each new cell in the developing fetus. From there on, hereditary mutations can continue to be passed down to future generations. While this may sound alarming, it is important to understand that not all individuals with an inherited mutation will develop cancer. However, these individuals do have a higher risk of developing cancer sometime during their lifetime.
Statistics indicate that approximately five to ten percent of all cancers are due to an inherited mutation, which is low. Research shows that there are certain indicators and cancer relationships that may point to prostate cancer as an inherited genetic mutation in some men. These factors include:
- Men who have been diagnosed with a Gleason Score of 7 or higher
- Men with prostate cancer who have a close family member with one of these cancers: female breast cancer (diagnosed at 50 or younger), male breast cancer, pancreatic cancer or ovarian cancer
- Family members with cancers connected to inherited gene mutations: colorectal cancer, kidney cancer, melanoma, retinoblastoma, thyroid cancer
In general, there are several other cancer-related characteristics that can also hint at the possibility of hereditary cancers in a family. These factors can include:
- Yourself or a family member being diagnosed with cancer before 50
- When an individual develops more than one type of cancer
- When specific cancers continue to be diagnosed in a family – example: breast, ovarian, uterine and colon cancer
- Bilateral cancer diagnoses: both breasts, both eyes or two internal organs such as both kidneys
- More than one child in a family diagnosed with cancer
- Families who have had similar cancers diagnosed throughout several generations
Genetic testing for hereditary cancers
At the Austin Center for Radiation Oncology, we offer prostate cancer patients (who meet the previously mentioned criteria) the option to undergo genetic testing for inherited gene mutations. The goal of genetic testing is help identify individuals whose family members may also be at risk for hereditary gene mutations. This information will help them make decisions about preventative screenings and treatment.
Positive results, after genetic testing, indicate that the individual and their family members are at a higher risk of developing certain cancers. These cancers and risk factors are as follows:
Male breast cancer – male family members have a risk of up to 60 times higher than the general population
Female breast cancer – female family members have a risk of up to 11 times higher than the general population
Prostate cancer – male family members have a risk of up to 2.5 times higher than the general population
Pancreatic cancer – male family members have a risk of up to 7 times higher than the general population; females are also at a higher risk of developing this cancer
Ovarian cancer – female family members have a risk of up to 44 times higher than the general population
Uterine cancer – female family members have a risk of up to 47 times higher than the general population
Colon cancer and Melanoma – both male and female family members are at a higher risk
(Statistics provided by Myriad)
It is important to understand that a positive result from genetic testing does not mean that you or your family members are destined to develop cancer. This diagnostic tool is important in letting family members know that the genetic mutation is present. With this information, they can work with their medical provider in making individual healthcare decisions.
Currently, ACFRO is offering genetic testing from the following vendors: Ambry, Invitae and Myriad. We encourage you to click on each company link to learn more about genetic testing, what each vendor offers, and what positive results can mean for you and your family. If you have been diagnosed with prostate cancer and would like to learn more about genetic testing, contact the Austin Center for Radiation Oncology.