Nav: Home

Ovarian cancer patients undertested for mutations that could guide clinical care

April 09, 2019

Fewer than a quarter of breast cancer patients and a third of ovarian cancer patients diagnosed between 2013 and 2014 in two states underwent genetic testing for cancer-associated mutations, according to a study by researchers at the Stanford University School of Medicine and several other organizations.

The findings indicate that substantial gaps exist between national guidelines for testing and actual testing practices. In particular, the findings show that too few women with ovarian cancer are tested for the presence of mutations that could be used to guide health care decisions.

The study looked at about 83,000 women diagnosed with breast or ovarian cancer in California and Georgia in 2013 and 2014.

"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," said Allison Kurian, MD, MSc, associate professor of medicine and of health research and policy at Stanford. "Now we can see that women with ovarian cancer are dramatically undertested. We also learned that between 8 and 15 percent of women with breast or ovarian cancer carry cancer-associated mutations that could be used to drive care decisions and influence family members' health care and screening choices."

Kurian shares lead authorship of the study, which will be published online April 9 in the Journal of Clinical Oncology, with Kevin Ward, PhD, MPH, assistant professor in epidemiology at Emory University. Lynne Penberthy, MD, MPH, associate director for the National Cancer Institute's Surveillance Research Program, and Steven Katz, MD, MPH, professor of medicine and of health management and policy at the University of Michigan, are co-senior authors.

Changing guidelines

Researchers have known for decades that inherited mutations or variations in certain genes, notably BRCA1 and BRCA2, increase the risk of developing breast and ovarian cancers. Genetic tests for mutations in BRCA1 and BRCA2 have been available for several years. But since 2013, genetic tests have incorporated many more potential cancer-susceptibility genes, and results have become much more complicated.

"Integrating genetic counseling and testing into the management of cancer after diagnosis has become much more challenging for patients and their clinicians," Katz said.

National guidelines recommend that all women with the most common type of ovarian cancer be tested for the presence of cancer-associated mutations; guidelines for testing breast cancer patients have been less expansive. Although the guidelines for genetic testing have expanded to include more patients diagnosed with breast or ovarian cancer and the more extensive multigene panel tests, it's not been clear to what degree these guidelines are followed in real-world clinical settings. Furthermore, the prevalence of known cancer-associated mutations in breast and ovarian cancer patients who are racial or ethnic minorities, as well as in the overall population, is unknown.

For the study, the researchers tapped the National Cancer Institute's Surveillance, Epidemiology and End Results Program, which tracks cancer diagnoses and outcomes in large populations across the United States. They linked data on cancer cases in California and Georgia with data from four laboratories conducting the majority of cancer genetic testing from 2013 to 2014. They found that only 24.1 percent of 77,085 women diagnosed with breast cancer and 30.9 percent of 6,001 diagnosed with ovarian cancer underwent any genetic testing.

Disparities in genetic testing

The researchers also observed disparities in testing, particularly among ovarian cancer patients. Although nearly 34 percent of non-Hispanic white women were tested, only about 22 percent of black women and 24 percent of Hispanic women were tested. Income and insurance status played a role in the prevalence of testing among women with ovarian cancer from all racial and ethnic groups, the researchers found. About 20 percent of patients with Medicare were tested compared with about 34 percent of patients with other forms of health insurance. Testing prevalence decreased to about 20 percent in areas where residential poverty equaled or surpassed 20 percent, and it was about 38 percent in regions where the poverty level was less than 10 percent.

The researchers found that among women with breast cancer in the study who underwent testing for a panel of guideline-designated genes, the prevalence of mutation variants of unknown significance was much higher in minority patients: 28.5 percent, 26.6 percent and 19.3 percent in African-American, Asian and Hispanic patients, respectively, versus 14.5 percent in non-Hispanic whites. The prevalence of pathogenic variants also varied along racial and ethnic lines.

"These differences underscore the need to improve the clarity of genetic test results, especially for racial or ethnic minority patients," Kurian said.
-end-
Researchers from Information Management Services Inc. and the University of Southern California, as well as other researchers from the National Cancer Institute, also contributed to the work.

The research was supported by the National Institutes of Health (grants P01CA163233 and R01CA225697), the California Department of Public Health, the Centers for Disease Control and Prevention and the Cancer Registry of Greater California.

Stanford's departments of Medicine and of Health Research and Policy also supported the work.

The Stanford University School of Medicine consistently ranks among the nation's top medical schools, integrating research, medical education, patient care and community service. For more news about the school, please visit http://med.stanford.edu/school.html. The medical school is part of Stanford Medicine, which includes Stanford Health Care and Stanford Children's Health. For information about all three, please visit http://med.stanford.edu.

Print media contact: Krista Conger at (650) 725-5371 (kristac@stanford.edu)

Broadcast media contact: Margarita Gallardo at (650) 723-7897 (mjgallardo@stanford.edu)

Stanford Medicine

Related Breast Cancer Articles:

Breast cancer: AI predicts which pre-malignant breast lesions will progress to advanced cancer
New research at Case Western Reserve University in Cleveland, Ohio, could help better determine which patients diagnosed with the pre-malignant breast cancer commonly as stage 0 are likely to progress to invasive breast cancer and therefore might benefit from additional therapy over and above surgery alone.
Partial breast irradiation effective treatment option for low-risk breast cancer
Partial breast irradiation produces similar long-term survival rates and risk for recurrence compared with whole breast irradiation for many women with low-risk, early stage breast cancer, according to new clinical data from a national clinical trial involving researchers from The Ohio State University Comprehensive Cancer Center - Arthur G.
Breast screening linked to 60 per cent lower risk of breast cancer death in first 10 years
Women who take part in breast screening have a significantly greater benefit from treatments than those who are not screened, according to a study of more than 50,000 women.
More clues revealed in link between normal breast changes and invasive breast cancer
A research team, led by investigators from Georgetown Lombardi Comprehensive Cancer Center, details how a natural and dramatic process -- changes in mammary glands to accommodate breastfeeding -- uses a molecular process believed to contribute to survival of pre-malignant breast cells.
Breast tissue tumor suppressor PTEN: A potential Achilles heel for breast cancer cells
A highly collaborative team of researchers at the Medical University of South Carolina and Ohio State University report in Nature Communications that they have identified a novel pathway for connective tissue PTEN in breast cancer cell response to radiotherapy.
Computers equal radiologists in assessing breast density and associated breast cancer risk
Automated breast-density evaluation was just as accurate in predicting women's risk of breast cancer, found and not found by mammography, as subjective evaluation done by radiologists, in a study led by researchers at UC San Francisco and Mayo Clinic.
Blood test can effectively rule out breast cancer, regardless of breast density
A new study published in PLOS ONE demonstrates that Videssa® Breast, a multi-protein biomarker blood test for breast cancer, is unaffected by breast density and can reliably rule out breast cancer in women with both dense and non-dense breast tissue.
Study shows influence of surgeons on likelihood of removal of healthy breast after breast cancer dia
Attending surgeons can have a strong influence on whether a patient undergoes contralateral prophylactic mastectomy after a diagnosis of breast cancer, according to a study published by JAMA Surgery.
Young breast cancer patients undergoing breast conserving surgery see improved prognosis
A new analysis indicates that breast cancer prognoses have improved over time in young women treated with breast conserving surgery.
Does MRI plus mammography improve detection of new breast cancer after breast conservation therapy?
A new article published by JAMA Oncology compares outcomes for combined mammography and MRI or ultrasonography screenings for new breast cancers in women who have previously undergone breast conservation surgery and radiotherapy for breast cancer initially diagnosed at 50 or younger.
More Breast Cancer News and Breast Cancer Current Events

Top Science Podcasts

We have hand picked the top science podcasts of 2019.
Now Playing: TED Radio Hour

In & Out Of Love
We think of love as a mysterious, unknowable force. Something that happens to us. But what if we could control it? This hour, TED speakers on whether we can decide to fall in — and out of — love. Guests include writer Mandy Len Catron, biological anthropologist Helen Fisher, musician Dessa, One Love CEO Katie Hood, and psychologist Guy Winch.
Now Playing: Science for the People

#543 Give a Nerd a Gift
Yup, you guessed it... it's Science for the People's annual holiday episode that helps you figure out what sciency books and gifts to get that special nerd on your list. Or maybe you're looking to build up your reading list for the holiday break and a geeky Christmas sweater to wear to an upcoming party. Returning are pop-science power-readers John Dupuis and Joanne Manaster to dish on the best science books they read this past year. And Rachelle Saunders and Bethany Brookshire squee in delight over some truly delightful science-themed non-book objects for those whose bookshelves are already full. Since...
Now Playing: Radiolab

An Announcement from Radiolab