Let’s face it: A metastatic breast cancer diagnosis is scary. Unlike breast cancer, which has a very high survival rate—an average of 90% over five years—metastatic breast cancer isn’t curable.
But technology, treatments, and therapies are constantly improving, experts say, which means a metastatic breast cancer diagnosis is not an automatic death sentence.
“The most important thing to do in the face of a metastatic breast cancer diagnosis is to not lose hope,” says Karen Hendershott, M.D., fellowship-trained breast surgical oncologist at Arizona Oncology. “While we can’t currently cure metastatic breast cancer, we can treat it.”
Here’s what you need to know about life expectancy after a metastatic breast cancer diagnosis.
What is metastatic breast cancer, anyway?
Metastatic breast cancer, or stage IV breast cancer, is cancer that originated in the breast, but now, the cancer cells have spread beyond the breasts and lymph nodes to other parts of the body—most commonly, to the bones, lungs, liver, or brain.
Women who are diagnosed with metastatic breast cancer have typically recovered from breast cancer only to develop new symptoms years later, such as bone pain, shortness of breath, unexpected weight loss, or persistent fatigue, which signal the cancer cells have spread, says Danae Hamouda, M.D., associate professor of medicine and fellowship program director of hematology and oncology at The University of Toledo. “It is less common for women to be diagnosed with metastatic breast cancer without a prior history of a breast cancer diagnosis,” she says, adding that approximately one in 20 women receive an initial diagnosis of metastatic disease.
But not everyone who gets breast cancer later develops metastatic breast cancer. It’s estimated that somewhere between 3 and 30% of women who are diagnosed with—and cured of—breast cancer will later be diagnosed with metastatic breast cancer, according to Hamouda.
The type of breast cancer with which a woman is initially diagnosed is also a factor. For example, women who are diagnosed with hormone-sensitive breast cancer generally have a lower risk of metastatic breast cancer, but they can develop it “decades after their initial diagnosis,” says Hendershott. Women with hormone-incentive breast cancers have a higher risk of it spreading and becoming a metastatic disease. But in these cases, “the chance of becoming metastatic tends to peak within the first few years,” and is very unlikely after five years, Hendershott says.
Your life expectancy after a metastatic breast cancer diagnosis
“Once breast cancer has spread beyond the ‘local’ area and is metastatic, it is treatable but no longer considered curable,” says Hendershott. Eventually, treatments will fail. Metastatic breast cancer typically spreads microscopically to numerous areas, of the body, mutating in ways “that eventually allow them to escape the medications used to treat them,” Hendershott explains.
While the average survival rate of a breast cancer diagnosis is 90% over five years, that statistic tumbles for metastatic breast cancer, dipping to just 29% in the same time period, the most recent data shows. (Here’s what that means: A woman with metastatic breast cancer is 29% as likely to be alive in five years as a woman who does not have metastatic breast cancer.)
