Over 13 years, researchers from Massachusetts General Hospital (MGH), Stanford University and Beth Israel Deaconess Medical Center used multigene panel screens in 1069 women to look for non-BRCA1 or BRCA2 mutations.
The women who took part in the study were chosen because of their personal or family history in breast and ovarian cancers. Their samples were tested either with a 25- or 29-gene panel.
The findings, published in JAMA Oncology, showed that 40 women, or 3.8 percent of the total group, carried potentially harmful mutations. Twenty-six of these mutations were associated with low-to-moderate risk of breast or ovarian cancer, eight with Lynch syndrome, which is linked to colon and ovarian cancer risk, and three to other high-risk breast cancer genes (including CDH1 and PALB2).
Lead author Leif Ellisen, professor of medicine at Harvard Medical School, commented, 'If you actually look on a case-by-case basis, in the majority of women where you find these mutations, you really would change what you recommend to them for either screening or prevention of
He added: 'Even among all appropriate candidates who are sent for genetic testing, only nine percent will test positive for the BRCA mutations, so an additional four percent who have
Overall, including 23 women that were recruited later in the study, there were 63
However, some experts have expressed concerns about multigene testing, based on the fact that we might not be ready for incorporating poorly defined cancer mutations into clinical practice.
Dr Elizabeth Swisher, an obstetrics and gynaecology researcher from the University of Washington who wrote a commentary accompanying the study, noted a 'major argument against multigene testing has been the need to avoid harm by providing mutation information on genes for which guidelines about care management are not well defined'.
However, she concluded, 'We must continue to assess the effect of such tests on clinical care and patient experience... and work to provide meaningful guidelines for cancer-preventive care for those with less common genetic findings.'