A newly approved blood test can help identify cancer risk. Should you get it?

In 2023, the United States Food and Drug Administration approved the first blood test that can aid in identifying dozens of heredity variants linked to cancer risk. The test, called the Invitae Common Hereditary Cancers Panel, looks at 47 genes associated with hereditary breast, ovarian, uterine, prostate, colorectal, gastric, melanoma and pancreatic cancers.

If someone has one of these pathogenic gene variants, they may face increased risk at developing high-risk cancers that are hard to detect. Testing can help people detect and treat cancers at an earlier stage, which can increase their chances of having positive outcomes from treatment.

But who should be getting the test — and when? University of Chicago Medicine Licensed Certified Genetic Counselor Feighanne Hathaway, MS, LCGC, answers common questions about genetic testing for cancer.

Who should get genetic testing?

Traditionally, anyone should seek genetic testing for mutations if they or a close family member have one of the following:

• Diagnosis of a rare cancer (i.e., pancreatic, ovarian, male breast cancer)
• Any metastatic prostate cancer diagnosis
• Cancer diagnosis before age 50 (especially in a person's 20s or 30s)
• More than one cancer diagnosis in one family member
• Diagnosis of bilateral cancer in paired organs (like bilateral breast cancer)
• Three generations of cancer in a family
• Ashkenazi Jewish descent (regardless of family history)

That said, we encourage anyone who is concerned about cancer to get a risk assessment for cancer by a genetics expert. We are seeing more and more individuals who do not know their family history for a whole host of reasons. Family history should no longer be the only criteria when determining who is eligible for testing.

Is genetic testing available at UChicago Medicine?

Yes. In our Cancer Risk & Prevention Clinic, our genetic counselors and physicians offer genetic testing, use personal medical and family risk factors to assess cancer risk and discuss treatments options, screening recommendations and prevention methods. Along with other multi-gene panels, we have been offering the Invitae Common Hereditary Cancers Panel for many years, as it includes testing for mutations in BRCA1 and BRCA2 that have been FDA-approved for some time.

Which type of panel is best for me?

Most patients would benefit from the Invitae panel, since it is a larger panel. However, if there is a family history of a more rare cancer, I would order something slightly different. For example, for hematological malignancies, there are genes that are not included in the common cancer panel that I would add separately.

In general, we commonly order this panel through Invitae, and insurance carriers usually cover the cost. In addition, our UChicago Genetics Lab offers a similar panel for hereditary cancers, as do several other commercial labs.

What do you and other experts at UChicago Medicine think of this panel?

I am glad that a panel test is finally being approved as the best method for genetic testing, since we in the genetics community have been saying this for a long time. Genetic testing for hereditary breast cancer has moved beyond BRCA1 and BRCA2, yet insurance companies will only cover testing for these two genes.

In addition, trying to get insurance coverage for some of the more rare hereditary cancer syndromes has always been challenging. I hope that this new FDA approval will make it a bit easier to get expanded coverage for testing.

Additionally, I hope this increases coverage of genetic testing for genes beyond breast cancer risk. As a cancer genetics expert, I hope this allows us to expand genetic testing to more underserved populations, which may identify people who need additional screening for cancer and ultimately save lives.

Looking ahead, what can we expect to see in the field of genetics?

The field of genetics and genetic testing is growing at unprecedented rates. The concern now is that we have access to a vast amount of data, but our understanding of what to do with that data remains incomplete. We know many genes have associations with cancer, but exact risks are not always known. Screening and surveillance are not always available for rare cancers, so management is not always clear nor equitable across our own healthcare system.

Then there are the variants of uncertain significance, which are genetic changes that are unclear on whether they disrupt the function of the gene and lead to cancer; there is a 20% chance a patient will come back with this inconclusive result. These results are not clinically actionable, but we have seen clinicians in the community making drastic clinical decisions based on these. People who receive these inconclusive results should also have access to genetic professionals to discuss the most appropriate path forward.

I think we can expect more precision medicine in understanding one’s risk for cancer across many tumor types that goes beyond single gene testing. We will start to see more polygenic risk estimates for other tumor types, as well as genetic testing for modifier genes that might have a protective effect when one has a high-risk gene.

Fifteen years ago, genetic testing for hereditary cancer was primarily done to prevent cancer. Now, we know it can aid in treatment of cancer. I think this will start to expand over a broad spectrum of tumor types. We are already seeing more and more of this, and I think it will just continue to get more precise.