Genetic testing offers powerful weapon for detecting breast cancer: Sema4

While mammograms and physical exams have long been options offered to help women detect breast cancer, people with a family history of the disease could benefit from more proactive choices. Ken Onel, senior vice president of translational genetics with Sema4, spoke with Outsourcing-Pharma about the powerful tools and technology available to help patients, caregivers, and researchers pinpoint and fight the disease.

OSP: Could you please share an overview of how breast cancer detection and diagnostic testing have evolved in recent years?​

KO: Advances in imaging, such as tomosynthesis, have helped clinicians detect and diagnose breast cancer earlier than by traditional mammogram alone. The recognition that hereditary cancer testing can save lives and even change the health trajectory of families has led many primary care providers and OB/Gyns to perform testing to identify women at high risk for breast cancer (and other cancers as well).

As a result, these women can be followed closely so that, if they develop breast cancer, it can be caught early when it is most curable.

OSP: Specifically, how has genetic testing helped in detecting and preventing BC in at-risk patients?​

KO: About one in eight women will be diagnosed with breast cancer over the course of her life. Women who have what is referred to as a “pathogenic variant” in a gene associated with an inherited predisposition to cancer, such as BRCA1 or BRCA2, may have an increased lifetime risk of being diagnosed with breast cancer as compared to women in the general population. These women can be offered more intensive surveillance for breast cancer, starting at a younger age and using additional imaging modalities. This allows doctors to identify cancers at earlier stages when they are more treatable.

Some women also choose to take certain medications or to undergo risk-reducing procedures, such as prophylactic mastectomies, to reduce their risk of ever developing breast cancer.

OSP: Please share some detail of BRCA gene detection and understanding, and how other genes (you’d mentioned ATM, CHEK2, PALB2) also are important to bring into the discussion.​

KO: While one in eight women in the general population will be diagnosed with breast cancer over the course of her life, this proportion increases significantly for women with pathogenic variants in the BRCA1 or BRCA2 genes. These pathogenic variants can be identified by a woman’s doctor by performing genetic testing for hereditary cancer.

However, pathogenic variation in other genes such as ATM, CHEK2, and PALB2 are also associated with an increased risk for breast cancer and other cancers as well. Therefore, if a doctor chooses to order genetic testing for a woman s/he believes may be at increased risk for breast cancer because of her genetics, it is important to keep in mind that BRCA1 and BRCA2 are not the only genes associated with an increased risk for breast cancer, and so, for most women, it makes sense to order testing of a “panel” of genes.

OSP: Please talk about comprehensive hereditary tests—what does such a test involve, and what can it do for patients in helping them protect themselves against BC?​

KO: Genetic testing for hereditary cancer syndromes is very simple. A doctor orders a test for a patient, a sample of blood or spit is collected, and it is then sent to a laboratory. At the testing laboratory, a panel of genes that are associated with hereditary cancer are sequenced and the sequence of each gene is analyzed to determine whether the patient has a pathogenic variant that disrupts the normal function of the protein encoded by that gene. If so, that is called a “positive” result.

For women with a positive result, that individual’s doctor will then set up an ongoing personalized surveillance plan based upon the genetic testing results, as well her family history and personal medical history. The entire testing process typically takes about two to three weeks, and for most patients, is covered by insurance.  

OSP: Could you please discuss why men shouldn’t count themselves out of this conversation?​

KO: Variants in genes associated with breast cancer in women are often also associated with an increased risk for certain types of cancers in men as well. Sometimes, this even includes an increased risk for male breast cancer. Moreover, each child – male or female – of a parent – father or mother -- with a pathogenic variant in a hereditary cancer gene has a 50% chance of inheriting that variant. So, both for their own health and for their children’s health, men need to be part of the conversation and should discuss genetic testing with their doctor.

OSP: Why is it important for patients to broach the subject of hereditary testing when they talk to their doctors? Also, is it something that doctors remain uninformed about, to some extent?​

KO: Even though it has such important implications for both patients and their families, unfortunately, hereditary cancer testing is not part of the standard of care across specialties. Doctors may not know how to order a genetic test or what test is best for their patient, and they may also be unsure about what to do with the results.

It is important for the patient to proactively ask about hereditary testing if their doctor doesn’t raise the topic. This information can be life-saving.

OSP: How can Sema4’s solutions help in BC identification and management??​

KO: Sema4 Signal is our portfolio of precision oncology solutions to enable providers to identify patients at high risk for breast cancer and other cancers create a personalized plan to lower their risk for cancer, detect cancer at an earlier and more treatable stage, and help family members who may also be at increased risk. Importantly, we not only help families through genetic testing but also enhancing care by making available to patients and providers trained Genetic Counselors who can help doctors develop personalized surveillance plans for their patients.

Our solutions also help patients who are diagnosed with cancer by allowing their doctors to identify ways to attack the cancer using new targeted therapies and immunotherapies. The hope is that these novel treatment strategies attack a specific cancer while sparing the patient the side effects of chemotherapy or radiation therapy. Our aim is to deliver the information needed to patients and providers to drive better care across prevention, treatment, and long-term monitoring.