Newsroom

August 27, 2019

Ambry Genetics’ Data Reveal that Expanding Genetic Testing Guidelines Could Identify More Patients with Increased Risks of Cancer

Study finds that current guidelines exclude too many and test too narrowly, and reveals several new gene-cancer associations with potential to impact patient care.

(Aliso Viejo, CA) August 27, 2019: Ambry Genetics (Ambry), a leading clinical genetics testing company, announced today new opportunities to improve genetic testing guidelines. In the largest cohort study of its kind, Ambry presents novel, detailed evidence on how to improve the guidelines to identify more at-risk patients.

Clinicians use guidelines to inform decisions about which patients should receive genetic testing for hereditary cancer and for those patients which genes should be tested. These guidelines also have implications for how insurance plans cover genetic testing, and for appropriate medical man-agement of patients after testing is complete.

In their recent study published in Genetics in Medicine, researchers from Ambry and Mayo Clinic applied genetic testing criteria from the National Comprehensive Cancer Network Clinical Prac-tice Guidelines in Oncology to 165,000 patients who underwent multigene, hereditary cancer panel testing.

Ambry specifically looked at the testing guidelines for BRCA-Related Breast and/or Ovarian Can-cer Syndrome (HBOC) and for Lynch Syndrome to better understand how the guidelines for these two common, inherited conditions might be improved to identify more at-risk patients.

The study found that updating the BRCA1 and BRCA2 and Lynch syndrome testing criteria to include more medically actionable, cancer-predisposition genes – and relaxing current criteria, such as age-at-diagnosis constraints – would identify more patients at risk for developing heredi-tary cancer.

The study found that:

• 1 in 4 (409/1518) patients with pathogenic variants in Lynch syndrome genes would have been missed using current Lynch syndrome testing criteria;

• 1 in 17 (302/5200) patients with pathogenic variants in BRCA1 and BRCA2 would have been missed using current BRCA1 and BRCA2 testing criteria; and

• 3 in 5 (7647/12,847) patients with pathogenic variants in clinically actionable breast and/or ovarian cancer genes would have been missed if tested for BRCA1 and BRCA2 only.

“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 preventive surgeries,” said Holly LaDuca, lead author on the study and senior manager of Clinical Affairs Research at Ambry Genetics.

In addition, this study revealed several new gene-cancer associations that have the potential to impact patient care. For example, pathogenic variants in BARD1 were associated with a 2-fold increased risk for breast cancer. However, there are no recommendations for increased breast cancer surveillance for these variants like there are for other genes associated with similar risk.

“Results from this study refined several gene-cancer associations for which there are no recommendations for increased surveillance and/or preventive surgeries. More studies are needed from the genetics community to better understand how these new gene-cancer associations have the potential to impact patient care,” added Ms. LaDuca.