Breast cancer treatment isn’t exactly made to order. But it is more personalized than ever.
Breast Cancer treatment options can vary a little or a lot from one woman to the next. It all depends on her cancer’s genetic and cellular features; her age, health, and medical history (including inherited genetic mutations that can lead to breast cancer); and other factors, like the size of her tumor, how fast it’s growing, and how far it has spread.
Chemo may not even be part of the equation, thanks to new breast cancer treatments targeting specific hormones and proteins involved in the progression of her disease.
“We’re taking the whole patient into consideration to say, ‘This is what we think yourbest treatment would be’,” says Janna Andrews, MD, a board-certified radiation oncologist and assistant clinical professor at the Zucker School of Medicine at Hofstra/Northwell in Hempstead, New York. “And it may not be what your neighbor would get,” she adds.
Breast cancer treatment is typically a team effort. A breast surgeon (or surgical oncologist) removes the woman’s tumor. A radiation oncologist may administer radiation to kill any remaining cancer cells or shrink the tumor. Chemotherapy or other anti-cancer medications (such as hormone therapy and targeted drugs) are prescribed by the patient’s medical oncologist. And, if breast reconstruction is involved, a plastic surgeon may play a role, too.
In addition to or instead of standard treatments, some women may be eligible to enroll in a research study, known as a clinical trial, to test experimental therapies. There are hundreds of breast cancer trials taking place across the U.S. involving novel drugs, drug combinations, procedures, and imaging techniques.
Experimental or not, every woman ought to consider the pros and cons of any intervention that her oncology team recommends. Here, we briefly explain standard treatments (and a few that appear promising) along with their benefits and drawbacks.
Surgery is a mainstay of breast cancer treatment. What’s changed over the years is the type of surgery. Many women now have breast-conserving surgery, called lumpectomy. The surgeon cuts out the tumor and some of the surrounding tissue while sparing as much healthy breast tissue as possible.
Mastectomy—removal of the entire breast—is less common. Variations on this surgery include partial mastectomy, which involves removing a large segment of the breast (larger than lumpectomy). When both breasts are removed, it’s called bilateral or double mastectomy. Skin-sparing mastectomy preserves the skin for breast reconstruction.
As with any surgery, lumpectomy and mastectomy pose potential risks for bleeding and infection.
Many women with breast cancer also undergo what’s called a sentinel lymph node biopsy. (A sentinel lymph node is the first lymph node–a gland that’s part of the immune system–likely to show any sign of cancer if, in fact, the cancer has traveled beyond the breast.) A sentinel lymph node biopsy can be performed either during breast cancer surgery or in a separate procedure, to see if and how far the cancer has spread from the tumor into the lymphatic system.
First, dye or radiation is injected into the breast. As it travels, it marks (by color or radioactivity) the first one to three underarm lymph nodes affected. These telltale nodes are then removed for analysis.
Alternatively, an axillary lymph node dissection may be performed. This type of surgery involves removing multiple lymph nodes from under the arm.
Lymph node surgery poses a risk of swelling in the arm or chest, called lymphedema.
William Gradishar, MD, the Betsy Bramsen professor of breast oncology at Northwestern University’s Feinberg School of Medicine in Chicago, says this complication is much less common now that fewer women are having full axillary dissections.
Many women with breast cancer receive radiation therapy. These high-energy treatments damage cancer-cell DNA so that rogue cells cannot duplicate or repair themselves. It’s commonly used after lumpectomy and sometimes after mastectomy and in patients with cancer that has spread to the lymph nodes or nearby tissue. In rare cases, it may be used prior to surgery to shrink a large tumor.
External beam radiation—delivered by a machine outside of the body—is the most widely used type of treatment. What differs is the way in which it’s delivered, Dr. Andrews explains. If a woman has large breasts that hang, she might lie on her stomach for treatment. This can minimize the dose of radiation to her heart and lungs, Dr. Andrews says. If the woman’s breasts are small or she has lymph nodes involved, she might be treated lying on her back while performing a breath-holding technique to reduce radiation to the heart.
Fatigue is a common complaint after external beam radiation. And you could have a skin reaction. Any woman can notice tanning or a burn from radiation, even if she’s not fair skinned, Dr. Andrews says, but it will fade away a few months after treatment.
There are several radiation therapy alternatives involving different delivery methods and dosing schedules. One relatively new option is called intraoperative radiation therapy. The patient receives a single dose of radiation inside the body during surgery to the area where the cancer resided. Another, called brachytherapy, involves inserting a catheter or balloon that delivers radiation to the area where the cancer was removed.
If you are pregnant, your doctor will likely wait until after you deliver to administer radiation.
Chemotherapy is a type of drug treatment embraced for its cancer-killing properties but loathed for its temporary side effects, like nausea, vomiting, fatigue, and hair loss. Many different chemotherapy drugs and drug combinations may be used for breast cancer. Some are given intravenously; others come in pill form. While chemo remains a powerful tool in the breast cancer treatment arsenal, it’s not always necessary.
Recently, a large study in the New England Journal of Medicine found that many women with early-stage breast cancer, especially those over age 50, can safely skip chemo treatments altogether. These women do just as well with hormone treatment alone, the study found. (More on hormone therapy later.)
“If you’re under the age of 50, the results are not as crystal clear about lack of benefit for chemotherapy, so you have to individualize it,” explains Dr. Gradishar, who chairs the National Comprehensive Cancer Network’s breast cancer guidelines panel.
When there’s a question about whether chemo would be beneficial, doctors can order tests like Oncotype DX or MammaPrint, among others. These tests analyze genes from a woman’s tumor biopsy. The results can help to predict who would likely benefit from a course of chemo and who would not.
Chemotherapy may be recommended after surgery to lower the risk of a cancer returning. It may also be used to shrink large cancers before surgery. And it remains the go-to therapy for women with advanced or aggressive cancers.
Triple negative breast cancers (which test negative for three key drivers of breast cancer) “actually respond very well to chemotherapy,” Dr. Andrews says.
Chemo isn’t given to pregnant women during their first trimester due to potential harm to the unborn baby. Treatment may be delayed until later in the pregnancy or after the baby is born.
Two out of three breast cancers are fueled by hormones in the blood. Women with these types of cancers are given medicines called hormone therapy to slow or stop tumor growth.
“Hormone therapy is actually a misnomer,” Dr. Gradishar says. “It should be anti-hormone therapy.”
Hormone-sensitive tumors have “receptors” that attach to either estrogen, progesterone, or both. To determine if yours is estrogen receptor-positive (ER-positive) and/or progesterone receptor-positive (PR-positive), a tissue sample will be removed and tested.
Taking hormone therapy can reduce the risk of a cancer recurrence. Women whose cancer has recurred or spread to other parts of the body may also benefit from taking these medicines.
Tamoxifen is a commonly prescribed hormone therapy. It works by stopping estrogen from binding to estrogen receptors. Although generally well tolerated, tamoxifen poses a tiny risk of uterine cancer as well as a small risk of blood clots, Dr. Gradishar notes.
Aromatase inhibitors are another type of hormone therapy. These drugs interfere with estrogen production, so they’re mostly given to women who are already in menopause. Side effects include bone thinning and joint and muscle pain.
This treatment category includes drugs that take aim at specific cancer-cell features. Hormone therapy was the first targeted therapy. Here are some other known breast cancer targets and their approved treatments. (Note: No targeted therapy is recommended for pregnant women with breast cancer because these drugs can harm the unborn baby.)
As many as one in five women with breast cancer has an excess of a protein called HER2 (human epidermal growth factor receptor 2) on the surface of her breast cancer cells. HER2-positive breast cancers tend to grow quickly and aggressively.
There are two types of treatments for these cancers.
Lab-produced antibodies (called monoclonal antibodies) target and thwart the HER2 protein. The IV drug trastuzumab (Herceptin) is one such drug. It is commonly given to women with early- or late-stage HER2-positive breast cancer. Another, called pertuzumab (Perjeta), may be added as well. If a woman has metastatic disease, she might be treated with an IV drug called ado-trastuzumab emtansine (Kadcyla).
All three of these medicines pose a potential risk of heart problems, among other side effects.
Kinase inhibitors are another type of HER2 treatment. These drugs block signals needed for tumor growth. Women with early-stage HER2-positive breast cancer who’ve completed trastuzumab treatment might take a once-daily pill called neratinib (Nerlynx). Another, called lapatinib (Tykerb), is approved for the treatment of advanced or metastatic HER2 breast cancer.
Diarrhea is a common side effect of these drugs. Less often, they can cause heart and lung issues.
CDK4 and CDK6
Certain proteins in the body called cyclin-dependent kinases (CDK) allow cancer cells to divide and multiply. CDK4 and CDK6 inhibitors are designed to thwart that process.
There are three approved drugs in this class of targeted therapies: palbociclib (Ibrance), ribociclib (Kisqali), and abemaciclib (Verzenio). These pills are prescribed to certain women with hormone-receptor positive, HER2-negative metastatic breast cancer.
“They improve the time until the disease progresses compared with anti-hormone therapy alone,” Dr. Gradishar says.
Common side effects include low white and/or red blood cell count, nausea, fatigue, and diarrhea.
PARP (poly ADP-ribose polymerase) is an enzyme in cells known to play a role in repairing damaged DNA. Scientists have found that blocking PARP in women with a mutated BRCA gene (BRCA1 or BRCA2) can frustrate cancer-cell repair and hasten the death of these rogue cells.
Anemia is a common side effect of this targeted medication. It’s also associated with blood and bone marrow cancers.
What if there were a way to coax your immune system to launch its own attack against cancer cells in your body? That’s the idea behind immunotherapy (also known as biologic therapy).
Currently, there is no FDA-approved immunotherapy for the treatment of breast cancer. But there are scores of different treatments in clinical trials.
These include cancer treatment vaccines, immune checkpoint inhibitors (which are drugs that help the body recognize and attack cancer cells), and something called adoptive cell transfer, an approach that uses a person’s own immune cells to fight the disease.
A recent report in the journal Nature Medicine describes a modified form of adoptive cell transfer that seemingly helped a woman with advanced breast cancer. Researchers at the National Cancer Institute identified her tumor mutations and matched them to immune cells in her body that might recognize the mutated proteins. The selected immune cells were then grown in the lab to create an army of cancer-killing cells, which were infused back into her body. More than two years post-treatment, she remained cancer-free, according to the report.
“Immunotherapy is unlikely to be given by itself. It’s going to be given with the other standard therapies, and that’s assuming that the results are positive,” Dr. Gradishar says.
These treatments also have potentially onerous side effects that vary from drug to drug, including flu-like symptoms and allergic reactions.