The American Cancer Society (ACS) estimates 281,550 women will be diagnosed with breast cancer in 2021. The average risk for a woman developing breast cancer in her lifetime is 13 percent, or a 1 in 8 chance, according to the ACS.
Breast cancer is the most common form of cancer among women.
For many women, a diagnosis of breast cancer could also include that it has metastasized or spread to other areas of her body (typically the liver, lungs, bones or brain).
A diagnosis of metastatic breast cancer can be overwhelming and frightening. Advances in treatment, however, provide women a way to manage the disease and live productive lives for many years.
“The good news is that there is so much research for breast cancer that we have all of these great treatment options that have been changing the outcome for patients,” says Amaryllis Gil, M.D., a hematologist and oncologist and Associate Medical Director of Elmhurst Hospital’s Nancy W. Knowles Cancer Center.
Though the cancer has spread to other areas of the body, treatment for metastatic breast cancer still focuses on the origination point. A diagnosis will include testing to determine what type of breast cancer someone has, if the BRCA1 or BRCA2 mutations are present and next-generation sequencing to treat any mutations in the cancer cells.
Typically, breast cancers are treated according to the receptors on the cancer cell surface. Treatments may include chemotherapy, immunotherapy and/or targeted therapy. If being treated for a BRCA1 or BRCA2 mutation, targeted therapy is often used.
Treatment, however, varies depending on the type of cancer:
- Triple-negative breast cancer makes up about 15 percent of all breast cancer cases. Among triple-negative breast cancer cases, about 20 percent have a BRCA1 or BRCA2 mutation. For women who no longer are responding to typical chemotherapy drugs, monoclonal antibody chemotherapy drugs provide a way to directly target the cancer cells.
- Hormone receptor-positive cancers (estrogen receptor-positive or progesterone receptor-positive) make up 2 out of 3 breast cancer cases, according to the ACS. In these types of cancers, cancer cells have receptors for estrogen or progesterone cells to help the cancer spread. A hormone blockade, with an oral drug like tamoxifen or an aromatase inhibitor, can help block the receptors and keep the cancer from growing. For premenopausal women, treatment may also include inducing menopause either through monthly injections or surgery to help suppress hormones. Treatment may also involve the use of CDK4/6 inhibitors or a P13K inhibitor (for particular mutations). Chemotherapy may be used if hormone therapy fails.
- Triple-positive cancers (ER/PR-positive and HER2-positive) involve some of the same treatments as hormone receptor-positive cancers, such as a hormone blockade. Targeted therapy delivered through a monoclonal antibody, trastuzumab, attacks the HER2 protein in this cancer. Pertuzumab may also be added to the treatment. If the cancer progresses, the care team may focus primarily on the HER2 and discontinue the hormone therapy.
- HER2-positive cancers can be aggressive in nature, but there are many effective therapies, Dr. Gil notes. In the past, chemotherapy was the main option, but today targeted monoclonal antibody treatments, such as trastuzumab or pertuzumab, are paired with chemotherapy agents through an intravenous treatment that is delivered every three weeks.
Stage IV treatment options are palliative, not curative, in nature, Dr. Gil says. But with advances in treatment options, she says many patients are seeing their prognosis outlooks described in years, not months.
“There’s been an explosion in treatment options,” she says, adding that controlling the cancer and its symptoms helps improve a patient’s quality of life. “There is better supportive medicine and better supportive care for patients.”
For more information, visit EEHealth.org/services/cancer/breast-cancer-center.