Study Shows Genetic Testing Beats Traditional Methods for Detecting Cancers

Breast Cancer Genetic Testing Beats Traditional Cancer Detecting Methods

Cancer, especially breast cancer, has many ways to be identified, but usually not until it is too late. Most traditional methods for testing for cancer are only done after cancer has already developed and is effecting a person’s health and it’s a possibility that cancer may be the cause. Clinicians use guidelines to help them make informed decisions about which patients should receive genetic testing, and of those, what genes should be tested. As a preventative course of action or discovering what precautions need to be taken, genetic testing is the only way to identify any of these. A study by Ambry Genetics that showed that 60% of clinically actionable breast cancers and ovarian cancers would have been missed if not for genetic testing. Do those guidelines hold true across other areas of cancer detection ?

Common Genetic Tests Used to Identify Breast Cancer Risks

Genetic testing can identify the predisposition to developing breast cancer. Two of the most common genes that can contribute to the development of breast cancer are BRCA1 and BRCA2. These are both caretaker genes that repair damaged DNA and if they cannot repair it, destroy the damaged cells. Mutations in the BRCA1 and BRCA2 are linked to the inability to properly repair damaged DNA, and this increases the chances of developing breast cancer. 

The most common genetic tests for breast cancer are also linked with testing for predisposition for ovarian cancer, as well. Doctors also test patients who have Lynch Syndrome as well. Those with Lynch Syndrome are predisposed to developing breast and ovarian cancer, even without having other genetic variations. Current testing guidelines restrict doctors to who they can test when they can test and are very defined test panels for detecting variations in the BRCA1 and BRCA2 genes. The study conducted by Ambry Genetics showed how the restricted method of testing guidelines has become archaic in detecting other established anomalies that can also lead to the development of breast cancer. 

Ambry Genetics’ Study and How It Has Proven Breast Cancer Genetic Testing Guidelines Need to be Redefined

According to Ambry’s study found that there’s a necessary need to update the current BRCA1, BRCA2, and Lynch Syndrome testing criteria to include more cancer-predisposition genes and to relax the current testing criteria and in doing so it would identify more patients who are at risk for developing hereditary cancers. 

Ambry’s study found that doctors and clinicians adhering to the current testing guidelines are missing variants in each area of testing that would identify those that are genetically predisposed to developing cancer. 

Ambry’s study found:

  • 1 in 4 patients with genetic alteration in Lynch syndrome genes would have been missed if the current Lynch Syndrom testing criteria were to be continuously used</li>
  • 1 in 17 patients with genetic alterations in BRCA1 and BRCA2 would be missed using the current testing criteria for discovering pathogenic variants in BRCA1 and BRCA2.
  • 3 in 5 patients with genetic alterations in clinically actionable breast and/or ovarian cancer genes would have been missed if patients are only tested for BRCA1 and BRCA2 mutations

“This study identifies specific opportunities to expand the current testing guidelines to identify more individuals facing increased cancer risks, who would benefit from more intensive cancer surveillance and/or preventative surgeries,” sad Holly LaDuca, lead author on the study and senior manager of Clinical Affairs Research at Ambry Genetics.

In addition to pointing out large flaws in the current testing guidelines, this study also revealed several new genetic cancer associations that can further impact patient care. Genetic alterations in BARD1 were linked to a 2-fold increase predisposition to developing breast cancer. Currently, there are no recommendations for increasing breast cancer surveillance in patients with this variant. There are however methods for increased surveillance for breast cancer in patients who have other identified risks similar to those who have a genetic alteration in their BARD1. 

Even with the normal testing methods that are in practice today, it is not enough and broader testing methods have to be implemented, and the same processes set up for monitoring possible cancer development in those who have other recognized genetic alterations. 

Breast Cancer Surveillance: the Cost of Early Detection

Typical breast screenings do not start until age 45 for women who are at average risk for developing breast cancer. The most typical form of breast cancer screening is mammograms. While mammograms work for women older in age, they are harder to use on younger women, and cannot be used on most men. Although males can develop breast cancer, it is rare, but can still require screenings depending on their genetic background and any variants they may possess. Esteemed breast cancer surgeon Dr. Susan Love said that looking for breast cancer in a young woman’s mammogram is like “looking for a polar bear in the snow.” Younger women also develop breast cancer and can develop it earlier based on their predisposition and if there are one, or more genetic factors working against them. 

According to the breast cancer screening guide from Memorial Sloan Kettering Cancer Center women with a predisposition to breast cancer should receive a clinical breast exam every 6 months starting at age 25, an annual mammogram, and a possible annual MRI. The average cost of a mammogram for an uninsured patient is $102. While younger women may require an ultrasound due to having denser breast tissue which at an out-of-pocket costs is around $250. Depending on what a doctor recommends, an annual breast MRI may also be required, which is around $1000 per MRI. The cost of monitoring possible breast cancer development in women who are predisposed can be up to $1,600 a year for an insured patient who is predisposed to breast cancer. Now, those costs may be less if a patient has insurance, but breast cancer predisposition can be extremely time and money consuming. If patients receive genetic testing, they can determine their best course of monitoring with facts about their predispositions and develop a  treatment and monitoring plan that works best for them as determined between them and their doctor. 

How Broadening Genetic Testing Guidelines Will Cut Costs Later

Broadening guidelines for genetic testing can lead to increased prevention and raising awareness of the benefits of genetic testing for cancer. Patients who are aware of their predisposition and undergo regular scans and imaging have a better chance of catching any benign, or possible malignant tumors and a higher chance or earlier detection of any cancer. 

Early detection of breast cancer means a higher chance of survival, more treatments are available, and a better quality of life. Although breast cancer risks increase with age, monitoring earlier can also make it easier to establish any changes that a patient notices in their breast tissue. Without the knowledge of their predisposition and just how closely to monitor any changes, many women don’t know that what they are experiencing could be early signs of breast cancer. While genetic testing and identifying predispositions at an earlier age does not mean that breast cancer cannot be developed, it empowers women to take their health into their own hands under the care of their doctor. Lifestyle changes can take effect earlier and other cautionary measures can be taken to help catch breast cancer earlier than if the predispositions hadn’t been identified.