ASCO News: Young Women With Advanced Breast Cancer Benefit From a New Combination of Drugs

Specifically, the women who participated in the study (all of whom were younger than 59 and had not gone through menopause), lived almost two years without their cancer getting any worse when they took the two drugs combined. The women who only took the hormone drugsincluding Goserelin (Zoladex), tamoxifen (Soltamox), letrozole (Femara), or anastrozole (Arimidex)only lived about one year without their cancer getting any worse. And three and a half years after beginning the combined treatment, 70 percent of women were still alive, compared with only 46 percent of the women who only had the hormone therapy.

What this means is that, overall, the women who took the combination were 29 percent less likely to die from their breast cancer than the women who took the hormone therapy alone.

Ribociclibthe drug that was added to the hormone therapy–is a relatively new type of treatment called a CDK 4/6 inhibitor that works by targeting CDK 4/6 proteins that make it possible for cancer cells to grow and divide.

"These drugs are very synergistic with hormone medications, and are primarily used for hormone receptor-positive breast cancer," Dr. Erica Mayer, a medical oncologist and clinical investigator in the Breast Oncology Center at the Dana-Farber Cancer Institute, previously explained to SurvivorNet. This is exactly what doctors are seeing in the results from the ribociclib and hormone therapy combination.

One of the reasons these new findings are so encouraging is the fact that they were seen in a younger-than-usual group of women with advanced breast cancer. Pre-menopausal women can sometimes face more difficult outlooks, because their cancers have been known to be more aggressive than those diagnosed in women after menopause. But with more women being diagnosed with breast cancer at an earlier age than years past, testing new treatments in this age group has never been more important.

Because the effectiveness of this new drug combinationand other combinations either being studied or already approveddepend on specific characteristics of a woman's breast cancer, such as hormone receptors and HER2 receptors, it is important to have comprehensive tests done as soon as you're diagnosed.

And now that we're seeing these encouraging results with the combination of ribociclib and hormone therapy, the next step will be for doctors to determine who, exactly, is most likely to benefit from the new treatment. This requires researchers to a closer look at the specific DNA makeup of breast cancer, which they do by genetically sequencing tumors.

Dr. Elizabeth Comen, a medical oncologist at Memorial Sloan Kettering Cancer Center and a medical advisor to SurvivorNet, previously explained to us how genetic sequencing works, and why it's an important option for women with breast cancer. "We take the tumor, a piece of the tumor, and we look at all the genes that help make up the blueprint of that tumor," she said. "And then we try to figure out, what are the mutations that evolved in that cancer, specifically to allow it to grow? And the reason why that’s important is it might make certain clinical trials appropriate for a patient."

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