A 5-Minute Quiz Revealed Olivia Munn’s Breast Cancer Risk. You Can Take It Too

Olivia Munn recently revealed in an Instagram post that a free, easy tool saved her life. Her ob-gyn used a questionnaire designed to calculate a person's risk of breast cancer, which revealed Munn had an increased chance of developing the disease. That led to further tests and an early diagnosis of Luminal B cancer in both breasts and quick treatment.

The Breast Cancer Risk Assessment Tool, which her doctor used, isn’t new. It doesn’t involve any high-tech gadgets, doesn’t require a doctor, and doesn’t even cost anything. Experts say more women should know about it and complete it after they turn 35. Here's what to know.

What is the Breast Cancer Risk Assessment Tool?

Released in 1989 by the National Cancer Institute, the online questionnaire takes less than five minutes to complete and pretty accurately predicts a woman’s risk of developing breast cancer. "This calculator is a great first step that women can do on their own and discuss the results with their primary care doctor or gynecologist,” says Dr. Jennifer Litton, professor of breast medical oncology at MD Anderson Cancer Center.

It relies on a model built from many aspects of women’s health data including their age, their race and ethnicity, their family history of breast cancer, when they began their periods, and, if they have children, how old they were when they had their first one. The model matches these and other features with breast-cancer outcomes of women with similar characteristics and provides two risk assessments: a woman’s five-year risk of developing breast cancer, and her lifetime risk of the disease.

Read More: The Race to Make a Breast Cancer Vaccine

The questionnaire—also known as the Gail Model after its developer Dr. Mitchell Gail at the National Cancer Institute—is about 98% accurate in predicting risk of breast cancer in most women. It’s less accurate in women of color, who were less represented in the original model’s database, but the model is constantly updated and increasingly includes more information on a more diverse group of people. Overall, scores of 1.7% or above for five-year risk, and 20% or above for lifetime risk, indicate a higher risk that women should discuss with their doctors.

Who should take it?

Any woman between age 35 and 74 can take it to learn her risk, and about half a million women use it annually, according to the National Cancer Institute. It’s especially helpful for those who have a family history of breast cancer or for people who don't know their genetic risk for the disease or don't have major genes for breast cancer such as BRCA1 or BRCA2—which was the case with Munn. For women who fall into these categories, the tool can detect whether there are other factors that increase their risk.

“The vast majority of breast cancers aren’t related to BRCA mutations,” Litton says. “There are other environmental factors and lesser genes that, together with a perfect storm of other exposures, could lead to breast cancer. Breast cancer is the endpoint and there are millions of different ways to get there."

Read More: The Women Most Likely to Die of Breast Cancer Get the Least Attention

The tool was built on data from the Breast Cancer Demonstration Project, a screening study conducted in the 1970s involving 280,000 white women, and cancer data from the NCI Surveillance, Epidemiology and End Results Program (SEER). Additional data, including from Black women, were added from the Women's Contraceptive and Reproductive Experiences Study collected in the 1990s, and for Asian women from the Asian American Breast Cancer Study conducted in the 1980s, along with updated cancer incidence rates. Breast cancer data involving Hispanic women came from the San Francisco Bay Area Breast Cancer Study that collected data from 1995 to 2004.

People who want to learn more about their breast-cancer risk can also try another free online risk calculator called the Tyrer-Cuzick model, which relies on more recent data and provides similar predictions. At Memorial Sloan-Kettering Cancer Center (MSKCC), doctors often use both and go with the higher score to advise women. “We’re getting better and better at risk assessment,” says Dr. Larry Norton, medical director of the Evelyn H. Lauder Breast Center at MSKCC.

Where do mammograms fit in?

These questionnaires are not a substitute for regular mammograms, which women should start at age 40. But using them in addition to mammograms helps doctors to better advise women about the best ways of reducing their risk and ultimately helping them to avoid the more aggressive forms of the disease that are harder to treat, Norton says. “The object of these scores is to estimate a healthy woman’s risk of developing disease,” he says. “If that leads to earlier diagnosis, then that has [treatment] implications. Dealing with a small cancer"—one that doesn’t involve the lymph nodes—"is much simpler than dealing with a larger cancer that involves multiple lymph nodes.”

Read More: The Unique Hell of Getting Cancer as a Young Adult

Depending on what the scores reveal, doctors could make a number of changes, such as adding an MRI to the regular mammogram to enhance monitoring for potential tumors, or adding anti-estrogen medications to further lower a woman’s risk. In addition, “if they see higher risk, that might lead to a conversation that might include things like genetic counseling or genetic testing,” says Litton. Such testing could reveal additional genetic factors, other than BRCA, that might be contributing to a higher risk of breast cancer. Depending on which genes are involved, certain targeted therapies could lower the chances that those mutations could lead to advanced breast cancer.

Future innovations

Other risk-assessment tools are on the horizon. Machine-learning models are further refining the information gleaned from mammograms, and some are getting sophisticated enough to predict which currently normal scans show signs of potentially turning into malignant tissue in the future.

Even after a woman is diagnosed, tests such as OncotypeDx can predict whether she will benefit from adding chemotherapy, or whether her chances of remission are just as good using only anti-estrogen therapy. “It’s a very useful tool for helping some women avoid chemotherapy that they just don’t need,” says Litton.

But none of these tools are useful if women, and their doctors, don’t take advantage of them. “Roughly half of people are not getting any screening [with mammograms] at all,” says Norton. “The first step is to get what we currently have available to the general population. And then the ability to do risk-adjusted screening will further improve prognosis for patients."

"Knowledge is power, he adds. "The more you know about yourself, and the more you engage with medical professionals, the better you can get answers that are appropriate for you.”