Last week, actress and TV host Olivia Munn announced that she was diagnosed with breast cancer last year and has undergone four surgeries, including a double mastectomy. She thanked her doctors for using a breast cancer risk assessment tool (BCRAT) that helped lead to her diagnosis.

"I wouldn’t have found my cancer for another year—at my next scheduled mammogram—except that my OB-GYN, Dr. Thaïs Aliabadi, decided to calculate my Breast Cancer Risk Assessment Score,” wrote the 43-year-old actress on Instagram. “I hope by sharing this it will help others find comfort, inspiration and support on their own journey.”

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Last year, in an attempt to be proactive about her health, Munn took a genetic test that checks for 90 cancer genes. She tested negative for all cancers and received negative mammogram results as well.

At a routine follow-up a couple of months later, Munn’s OB-GYN (her “guardian angel”) suggested they calculate her BCRAT score, which showed that she had an increased risk of developing breast cancer during her lifetime.

That led to additional tests and the discovery that she had luminal B breast cancer in both breasts. This type of cancer is aggressive and accounts for about 15%  to 20% of breast cancers.

Munn said that if it hadn’t been for Aliabadi’s suggestion, she would not have found the cancer until her next annual mammogram.

Developed in 1989, the BCRAT is a questionnaire that uses a woman’s personal information to estimate her risk of developing invasive breast cancer within the next five years and within her lifetime, according to the National Cancer Institute (NCI).

The assessment asks about age, age at first menstrual period, age when a woman’s first child was born or whether the woman has not given birth, family history of breast cancer, past breast biopsies and results, race and ethnicity. 

Women are classified as being at high risk for breast cancer if they have a five-year risk of 1.67% or higher and a lifetime risk of 20% or higher.

Munn’s lifetime risk of 37.3% prompted additional imaging tests that aren’t recommended for women of average risk. In an interview on NBC’s Today, Aliabadi said that if Munn had not sought treatment, “her cancer would have grown.”

“I’m lucky,” wrote Munn. “We caught it with enough time that I had options. I want the same for any woman who might have to face this one day.”

The risk assessment tool has received a “dramatic increase in visits” since Munn’s announcement, an NCI spokesperson told NPR. To find out your BCRAT score, click here.

The calculator, however, is not appropriate for all women—for example, those with specific gene mutations or dense breasts—and it may underestimate the risk in certain Black and Latino women. In fact, it’s recommended that women speak with their doctors about completing the risk calculator.

To read more, click #Breast Cancer or Cancer Health’s Basics on Breast Cancer.  It reads in part:

Who gets breast cancer?

Breast cancer is the second most common cancer among women, after skin cancer. About 310,000 women are diagnosed with invasive cancer annually, according to the American Cancer Society. Men can also develop breast cancer, but this is rare. People with BRCA mutations are at high risk for breast cancer.

Around a quarter of women with early breast cancer will go on to develop metastatic disease. About 15% of breast cancer patients have hard-to-treat triple-negative breast cancer, which is more common among young women and Black women.

What are the symptoms of breast cancer?

The most common sign of breast cancer is a lump or mass. A hard and painless mass is most likely to be malignant, but cancerous tumors can sometimes be tender, soft or painful. Other symptoms may include breast swelling, skin irritation or dimpling, breast or nipple pain, nipple retraction (turning inward), redness, scaliness or thickening of the nipples or skin of the breast and discharge from the nipple.

How is breast cancer diagnosed?

Regular screening for breast cancer can detect the disease early when it is easier to treat. Professional guidelines vary in how often they recommend screening. The U.S. Preventative Services Task Force now recommends that women at average risk should start screening at age 40. All women and men who notice a new mass, lump or other changes in their breasts should report this to their health care provider.

If a mammogram detects changes in the breasts, an ultrasound may be done for further examination. Once diagnosed with breast cancer, MRI scans are usually done to assess the size of the tumor, look for additional tumors and determine whether the cancer has spread beyond the breasts.

A breast biopsy, or examination of a tissue sample, may be done to determine whether a tumor is malignant. Genomic testing of a tumor sample provides more information about the type of cancer and how best to treat it.