Less than 20% of patients with a history of ovarian cancer meeting National Comprehensive Cancer Network (NCCN) guidelines have undergone genetic testing or have discussed testing with their health care providers.
Fifteen percent of documented ovarian or breast cancer cases can be attributed to heritable mutations—such as BRCA1 or BRCA2—that provide valuable information for treatment and preventive care. However, limited data exist regarding the number of patients at high risk for these mutations who have not been genetically tested.
Christopher P Childers, MD, David Geffen School of Medicine, University of California at Los Angeles, and colleagues conducted a study to further identify risk of cancer in patients with a history of ovarian or breast cancer and to calculate the number of patients who failed to receive genetic testing. Researchers pooled cross-sectional data from three Cancer Control Modules of the National Health Interview Survey (2005, 2010, and 2015). A total of 47,218 adult patients were sampled with a history of ovarian or breast cancer who met 2017 NCCN eligibility criteria on the basis of age at diagnosis and family history.
Primary outcomes of the study included the proportion of individuals self-reporting a history of discussing genetic testing with their health care providers, being advised to undergo genetic testing, and undergoing testing for ovarian or breast cancer. Results were published in the Journal of Clinical Oncology (online August 18, 2017: doi:10.1200/JCO.2017.73.6314).
Among the 0.4% of women with a medical history of ovarian cancer, 15.1% acknowledged having discussed genetic testing with their health care providers, 13.1% of whom were advised to take the test. Of this 13.1% of patients, 10.5% underwent the test.
Similarly, 2.7% of the patients had a medical history of breast cancer, 29% reported having discussed the genetic test with their health care providers, 20.2% were advised to take the test, and 15.3% underwent the test.
Researchers estimated that approximately 1.2 to 1.3 million women in the United States who were likely to benefit from a genetic test did not take it. Recent changes in the NCCN guidelines, the lack of genetic counselors who are board-certified and specialized in cancer testing, uneven distribution of specialists across the nation, and the tendency of women to change their health care providers (which renders the new providers unaware of their patient’s history) are all viable reasons for this staggering statistic, researchers believe.
Large national efforts are warranted to address this unmet need, they concluded.—Zachary Bessette