Who Gets Breast Cancer and Who Survives?
Certain Tumors Are Less Treatable Than Others, and Doctors Know Your Odds of Getting Them
Doctors used to rely on staging — the size of the cancer and how far it had spread — to determine prognosis, but they now know that tumor type is even more important. "Different kinds of tumors have different 'personalities,' and each responds differently to treatment," says Eric P. Winer, M.D., director of breast oncology at the Dana-Farber Cancer Institute in Boston. About two thirds of all breast cancer tumors are hormone sensitive, which means they grow in response to estrogen. The good news: Women who have hormone-sensitive tumors have a higher survival rate because these tumors grow more slowly than other types and can often be prevented from recurring with hormone therapy.
Another 20 percent of all breast cancers have small amounts of a protein called human epidermal growth factor receptor 2 (HER2), which promotes tumor growth, says Winer. These HER2-positive tumors traditionally had a poorer prognosis because they tend to spread more quickly, but newer medications lower chances of recurrence.
The last approximately 15 percent of all breast cancer tumors are triple negative. They're more aggressive and more likely to recur than the others, says Winer, and they're also associated with the poorest survival rates.
Nearly Half of Women Don't Get Enough Chemo
Thirty years ago, if you had breast cancer, you got a mastectomy, period. "Even today, when most of my patients learn they have breast cancer, their first impulse is to say, 'Give me a mastectomy so I don't have to worry about it anymore,'" says oncologist Richard Bleicher, M.D., of Fox Chase Cancer Center in Philadelphia. But experts now agree that a more aggressive approach isn't necessarily better for treating early-stage cancer. In fact, a landmark study found that women with stages I and II breast cancer who had a lumpectomy with radiation were just as likely to survive as those who underwent a mastectomy.
Beyond surgery and chemotherapy, any long-term treatment depends on tumor type. For instance, women with early-stage hormone-sensitive cancers often take an anti-estrogen drug like tamoxifen, which reduces chances of recurrence by about half. Drugs like Herceptin and Tykerb are used to treat HER2-positive breast cancers; both work to block the HER2 protein that triggers cancer cell growth. These and other treatments are more successful than ever, but many sufferers aren't reaping the full benefits: A whopping 70 percent of women who had mastectomies were never told that less dramatic surgery, such as lumpectomy, was an option, according to a study commissioned by the American Society of Clinical Oncology. And up to half of all breast cancer patients may have received chemotherapy doses that were lower than the recommended levels.
"To get the best, most up-to-date treatments, make sure that all of the physicians you are seeing are experienced in treating breast cancer, whether it's your surgeon, your oncologist, or the radiation oncologist," says Winer. An option: one of the 64 NCI-designated comprehensive cancer centers across the country — these facilities are often involved in clinical trials and treat large volumes of breast cancer patients. (Find a center near you at cancercenters.cancer.gov.)