In the same way that BRCA1 and BRCA2 mutations helped pathologists identify women with increased breast cancer risks in the late 1990s, this new study isolates an additional 72 mutations medical laboratories may soon use to diagnose breast cancer and assess risk factors

For 20 years genetic scientists, anatomic pathologists, and medical laboratories have employed the BRCA1/BRCA2 genes to identify women at higher risk for breast cancer. And, because pathologists receive a high number of breast biopsies to diagnose, physicians and clinical laboratories already have collaborative experience working with genetic mutations supported by ample published evidence outlining their relationship with cancer.

Now, a global research study is adding 72 more mutations to the list of mutations already known to be associated with breast cancer.

In coming years, physicians and anatomic pathologists can expect to use the knowledge of these 72 genetic mutations when diagnosing breast cancer and possibly other types of cancers in which these mutations may be involved.

New Precision Medicine Tools to Improve Breast Cancer Survival

Combining the efforts of more than 550 researchers across 300 institutions and six continents, the OncoArray Consortium analyzed the DNA of nearly 300,000 blood samples. The analysis included samples of both estrogen receptor (ER-positive and ER-negative) cases.

Taken from a study published in the British Journal of Cancer, the graph above illustrates “proportions of familial risk of breast cancer explained by hereditary variants.” It is expected that anatomic pathologists will eventually incorporate these genetic variants into diagnostic test for breast and other cancers. (Graphic copyright: British Journal of Cancer.)

The results of their research were published in two separate studies: one in the scientific journal Nature and the other in Nature Genetics. The studies outlined 72 newly isolated genetic mutations that might help quantify the risk of a woman developing breast cancer in her lifetime.

Among the 72 mutations, seven genes were specifically associated with ER-negative cases. ER-negative breast cancer often fails to respond to hormone therapy. Thus, this discovery could be crucial to developing and administering precision medicine therapies tailored to specific patients’ physiologies and conditions. Treatments that improve patient outcomes and overall survival rates in ER-negative and ER-positive breast cancers.

Genetics Could Help Clinical Laboratories Wage War on All Cancers

According to data published by the Centers for Disease Control and Prevention (CDC), breast cancer is the most common form of cancer among women of all races. It’s the second-leading cause of all cancer deaths among most races and first among Hispanic women.

In the past, it was estimated that 5-10% of breast cancers were inherited through the passing of abnormal genes. However, Lisa Schlager, Vice President of community affairs and public policy for FORCE (Facing Our Risk of Cancer Empowered), told CNN, “This new information may mean that that estimate is low.” FORCE is a national nonprofit organization dedicated to fighting hereditary breast, ovarian, and related cancers.

Schlager calls upon health systems to “embrace the ability to use genetic information to tailor healthcare by providing affordable access to the needed screening and preventive interventions.” As precision therapy and genetic analysis continue to shape the way patients are treated, medical laboratories will play a significant role in providing the information powering these innovative approaches.

Furthermore, medical laboratories might leverage the same methods used by researchers to assess risk factors and identify genetic mutations and markers associated with other cancers. Douglas Easton, PhD, Director of the Centre for Cancer Genetic Epidemiology within the Department of Public Health and Primary Care at the University of Cambridge, and leader of the OncoArray Consortium investigation, explained to CNN that Illumina’s Infinium OncoArray is not limited to breast cancer, but is designed to work with other cancers, including:

·       colorectal;

·       ovarian; and,

·       prostate cancers.

Identifying Women at Increased Risk for Breast Cancer

Peter Kraft, PhD, Professor of Epidemiology at Harvard’s T.H. Chan School of Public Health, and a study author, told CNN, “Taken together, these risk variants may identify a small proportion of women who are at three-times increased risk of breast cancer.”

Kraft notes that samples were sourced from women of primarily European ancestry. Further study of other ethnic populations could lead to yet more mutations and indicators for cancers more common outside of the European region.

Research authors also highlight the importance of continued standard screening, such as mammograms. However, they suggest that genetic mutations, such as those found in the OncoArray study, might be used to highlight high-risk individuals and screen sooner, or conduct more in-depth genetic analyses, to catch potential cancer cases earlier and improve outcomes.

“Many women are offered mammogram screening when they are middle-aged,” Georgia Chenevix-Trench, PhD, co-author of the Nature Genetics study and researcher at the QIMR Berghofer Medical Research Institute in Australia, told LabRoots. “But if we know a woman has genetic markers that place her at higher risk of breast cancer, we can recommend more intensive screening at a younger age.”

Anatomic pathologists and clinical laboratories can use these new insights to offer increased options for oncologists and physicians on the front lines of the battle against cancer. While the list of genetic mutations related to cancer is far from complete, each added mutation holds the potential to power a new treatment, improve early detection rates, and improve survival rates of this global killer.

—Jon Stone

Related Information:

Major Study of Genetics of Breast Cancer Provides Clues to Mechanisms Behind the Disease

Breast Cancer Genetics Revealed: 72 New Mutations Discovered in Global Study

Identification of Ten Variants Associated with Risk of Estrogen-Receptor-Negative Breast Cancer

Association Analysis Identifies 65 New Breast Cancer Risk Loci

An Unprecedented Study Has Revealed 72 New Breast Cancer Gene Variants

Study Finds 72 New Genetic Mutations Linked to Breast Cancer

Major Study Identifies 72 New Genetic Risk Factors for Breast Cancer

Breast Cancer: 72 New Gene Mutations Uncovered