In a new study published in the journal Cancer, the myRisk hereditary cancer test by Myriad Genetics Inc, Salt Lake City, was shown to improve the detection of cancer-causing mutations by 46% in patients with breast cancer.
In the study, researchers at Beth Israel Deaconess Medical Center, Dana Farber Cancer Institute, and Massachusetts General Hospital Cancer Center used the myRisk test to determine the frequency of hereditary cancer mutations in 2,158 individuals with a history of breast cancer. Study participants included 1,781 patients referred for commercial BRCA1/2 testing and 377 patients with a personal and family history who previously tested negative for BRCA mutations.
Deleterious mutations were found in a total of 16 genes. Among the 1,781 patients referred for commercial BRCA testing, 9.3% carried a mutation in BRCA1 or BRCA2. Importantly, an additional 4% of patients carried a mutation in another breast and ovarian cancer susceptibility gene.
Among the 377 patients with personal and family histories who previously tested negative for BRCA mutations, the frequency of mutations in the other breast and ovarian cancer susceptibility genes was nearly 3%. Additionally, among the 1,781 patients referred for commercial BRCA testing, 0.4% of individuals had mutations in colon cancer (Lynch-syndrome) genes.
The myRisk hereditary cancer test increased the detection of cancer-causing mutations in genes other than BRCA1 or BRCA2 by 46% and found 43% more women with a deleterious mutation. Most of the new mutations were in other cancer susceptibility genes associated with breast or ovarian cancer, such as CHEK2, PALB2, and ATM.
“In this study, the Myriad myRisk hereditary cancer test identified significantly more genetic mutations that raise the risk of hereditary breast, ovarian, and other cancers,” says Nadine Tung, MD, director of the cancer risk and prevention program at Beth Israel Deaconess Medical Center. “These findings support the use of panel testing for some patients with breast cancer because it is much more efficient than testing one gene at a time, and may identify mutations in patients who are unaware of their family history of cancer. Patients should discuss their test results with a qualified healthcare professional and once they know their risk, they can take appropriate action to better manage their healthcare.”
The myRisk test uses next-generation sequencing technology to evaluate 25 clinically significant genes associated with eight hereditary cancer sites (breast, colon, ovarian, endometrial, pancreatic, prostate, and gastric cancers, and melanoma) to provide patients with information about their cancer risks.
“The myRisk test is rapidly moving us beyond testing for one gene at a time, making it possible to test multiple cancer-causing genes at once, which we believe will significantly improve patient care in this new era of genomic medicine,” says Anne-Renee Hartman, MD, vice president of clinical development at Myriad Genetic Laboratories. “Myriad is committed to advancing the science even further, and we are conducting several additional studies to develop evidence-based approaches to cancer prevention and risk reduction in these patients.”
For further information, visit Myriad Genetics.
Tung N, Battelli C, Allen B, et al. Frequency of mutations in individuals with breast cancer referred for BRCA1and BRCA2 testing using next-generation sequencing with a 25-gene panel. Cancer. 2014; published online first, September 3, 2014; doi: 10.1002/cncr.29010.