There are an estimated 2.8 million breast cancer survivors in the U.S., a testament to the more than 25-year decline in mortality, according to the American Cancer Society. Still, 231,000 women alone will be diagnosed with the disease this year, and about 40,000 will die.
These women will newly rely on targeted gene therapies, advancements in chemotherapy protocols and even preventive treatments. For breast cancer patients and their loved ones, the scientists who keep pushing the boundaries of what's possible are heroes held in highest esteem.
Here are the five biggest breakthroughs in breast cancer research those scientists have made in 2015.
1. A New Drug May Stop An Incurable Type Of Breast Cancer
The FDA granted accelerated approval to a drug called Palbociclib in February. When used with the breast cancer drug Letrozole in trials, Palbociclib was able to extend the amount of time study participants lived without their cancer progressing.
The cocktail was able to stop cancer progression in postmenopausal women with a treatable but incurable type of chronic breast cancer (ER-positive, HER2-negative advanced breast cancer) for an average of 20.2 months. A control group that only took Letrozole had an average of 10.2 months without cancer progression.
"It seemed to prolong the period of disease control significantly. More important is the promise it provides,” said Dr. Cliff Hudis, chief of breast medicine service at Memorial Sloan Kettering Cancer Center. "Maybe with more study, the drug will actually help people live longer; that’s the big answer we’re waiting for right now.”'
Hudis also praised Palbociclib because it is a less toxic form of treatment than chemotherapy. However, the FDA notes that serious side effects of the drug in combination with Letrozole include pulmonary embolism and diarrhea. Still, its approval is a heartening step for FDA watchdogs.
"The FDA approval strategy of breakthrough status and accelerated approval show the FDA’s commitment to getting promising drugs for serious diseases to patients faster,” said Dr. Julie Gralow, a member of the Fred Hutchinson Cancer Research Center and director of breast medical oncology at Seattle Cancer Care Alliance.
2. Genetic tumor testing will tell you if chemotherapy will work for you.
Researchers have known for some time now that a tumor’s genes can determine whether cancer patients will respond to chemotherapy. The Oncotype Dx test analyzes 21 genes in the tumor to determine whether or not the cancer is likely to recur, and whether or not chemotherapy will make a difference.
This test was created using historic data -- old tumors that grew in patients for whom outcomes were already known. But in September, the New England Journal of Medicine carried the very first study using data from current patients; it confirms the Oncotype assay is able to predict which treatments would be most effective in early stage, curable breast cancer patients. This helps women avoid toxic and unpleasant chemotherapy if the test reveals their cancers will not respond to it.
In an editorial that accompanies the study, Hudis noted that this protocol spared 1,626 women from receiving unnecessary chemotherapy. Each of them would have been a candidate for it according to traditional diagnostic standards.
"The key thing is that they identified a group of people who are normally candidates for chemotherapy but had a 99 percent freedom from metastases at five years," the typical benchmark for cancer survival, Hudis told HuffPost. "What it means practically is that some proportion of people who have been recommended to get therapy for years really don’t need it."
3. Less aggressive chemotherapy can still be effective.
Doctors already know that super aggressive chemotherapy, used in combination with a drug called Trastuzumab (or by its brand name, Herceptin), works to cure an early stage but aggressive type of breast cancer known as lymph node negative HER2+ breast cancer, a type that affects 15 to 20 percent of all breast cancer patients.
But in a study published in January in the New England Journal of Medicine, researchers found that a much less aggressive chemotherapy drug called Taxol, used in combination with Trastuzumab, was just at effective in helping women stave off breast cancer recurrence and death after three years.
"This trial showed that we can use less aggressive chemotherapy (weekly taxol) in combination with Herceptin in lower risk Her2+ breast cancers and still get excellent outcomes,” explained Gralow. "Trial designs that require less patients and are done faster like this need to be considered in the future, and trials looking at reducing toxicity for patients are also critical."
4. Bone strengthening medications can stop breast cancer's spread.
The most common place breast cancer will recur is in the bones, and research has gone back and forth on whether bone-strengthening medications called bisphosphonates, made to treat osteoporosis, can help prevent this.
Now, a meta-analysis of these studies published in the journal The Lancet confirms that these osteoporosis medications can reduce breast cancer recurrence in the bone and decrease deaths in postmenopausal women. Additionally, notes Gralow, the medications do what they were originally designed to do and have the added benefit of reducing fractures.
Hudis is more skeptical of the meta-analysis’ results, and notes that meta-analysis' positive results were all in middle-aged people or older who are candidates for bisphosphonate medication anyway. Younger breast cancer patients will need to have a more in-depth discussion with their doctors, he said. As with all medications, bisphosphonates can have serious side effects, like osteonecrosis of the jaw -- when the gum recedes and the jaw bone becomes exposed to air -- or eye inflammation and severe musculoskeletal pain.
5. Immunotherapy is showing more promise in the treatment of incurable cancers.
The odds are stacked against women with triple negative breast cancer, a type that accounts for 10-20 percent of all breast cancers. This kind of cancer is much more aggressive and also more likely to affect young women, black women, Latino women and those with the BRCA1 gene mutation, notes Johns Hopkins Medicine. As the name implies, these tumors do not have estrogen receptors, progesterone receptors or the HER2 growth factor, which means three avenues of targeted treatment are not an option for them. Only surgery, radiation therapy and chemotherapy can be deployed against this kind of tumor, and often to little effect, as the type is more likely to come back and spread.
But immunotherapy medication that activates a person’s own immune system against the tumor could one day be a promising therapy for triple negative breast cancer. For instance, a small study by Johns Hopkins researcher Dr. Leisha A. Emens found that an immunotherapy drug was able to halt the cancer’s progression for 24 weeks in 27 percent of participants. The study only had 54 participants, so the results are modest, but the drug’s promise is exciting. Emens presented the results of her study at the American Association for Cancer Research conference in April.
"It's early days, but that’s an area of really exciting, ongoing and rapidly expanding research,” said Hudis. "If it works, it’ll represent something new and important for triple negative breast cancer."
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