Patients With Ovarian Cancer Could Benefit From More Genetic Testing

Patients with ovarian cancer are undertested for the presence of mutations that could help guide healthcare decisions, according to research published in Journal of Clinical Oncology.

The researchers studied 83,000 women age 20 years and older with breast and ovarian cancer who had been diagnosed in California and Georgia in 2013 and 2014. There were 77,085 patients with breast cancer and 6001 with ovarian cancer. They found that there are substantial gaps between national guidelines for testing and the actual testing that occurs.

"We initiated this study—the largest population-based study of multigene testing in breast and ovarian cancer patients—because we wanted to see what cancer genetic testing and results looked like in the real world," Allison Kurian, MD, MSc, lead author and associate professor of medicine and of health research and policy at Stanford, said in a statement. "Now we can see that women with ovarian cancer are dramatically undertested. We also learned that between 8% and 15% of women with breast or ovarian cancer carry cancer-associated mutations that could be used to drive care decisions and influence family members' healthcare and screening choices."

While genetic tests for BRCA1 and BRCA2 mutations have been available for years to identify the risk of developing breast and ovarian cancers, incorporating genetic tests into management of cancer after diagnosis has been more challenging, noted coauthor Steven Katz, MD, MPH, professor of medicine and of health management and policy at the University of Michigan.

National guidelines recommend all women with the most common type of ovarian cancer are tested for the presence of cancer-associated mutations; however, the authors found that less than one-fourth (24.1%) of patients with breast cancer and one-third (30.9%) with ovarian cancer had genetic test results.

The researchers identified were genetic testing disparities. Testing, particularly among patients with ovarian cancer, was lower among black patients (21.6%) compared with white patients (33.8%) and lower among patients without insurance (20.8%) compared with patients with insurance (35.3%). There was also a gap based on where patients lived. In areas where residential poverty was at least 20%, testing prevalence was only about 20% compared with about 38% in areas where the poverty level was less than 10%.

“Substantial testing gaps and disparities among patients with ovarian cancer are targets for improvement,” the authors concluded.

Reference

Kurian AW, Ward KC, Howlader N, et al. Genetic testing and results in a population-based cohort of breast cancer patients and ovarian cancer patients. J Clin Oncol. 2019;37(15):1305-1315. doi: 10.1200/JCO.18.01854.