6 Key Breast Cancer Research Takeaways From the 2023 ASCO Annual Meeting


The 2023 ASCO Annual Meeting featured important updates on the CDK4/6 inhibitors for both early-stage and metastatic breast cancer, as well as research on new antibody-drug conjugates.

Written by Jamie DePolo

The 2023 American Society of Clinical Oncology (ASCO) conference in Chicago brought together more than 40,000 people engaged in all aspects of cancer research, care, and advocacy. The six-day meeting featured research presentations, posters, educational events, and networking opportunities. There were a number of presentations on breast cancer research, including several on the CDK4/6 inhibitors — Ibrance (chemical name: palbociclib), Kisqali (chemical name: ribociclib), and Verzenio (chemical name: abemaciclib).

Here are six important takeaways from the conference for people who’ve been diagnosed with breast cancer.

1. There are now two CDK4/6 inhibitors that offer benefits after surgery for hormone receptor-positive, early-stage breast cancer.

Results from the NATALEE trial found that treating early-stage, hormone receptor-positive, HER2-negative breast cancer with Kisqali plus an aromatase inhibitor after surgery reduced the risk of recurrence by about 25% more than treating it with an aromatase inhibitor alone. Kisqali is not yet approved to treat early-stage disease, but Verzenio is. The results suggest that you and your doctors may soon have a choice of CDK4/6 inhibitors for early-stage disease, so you can make treatment decisions based on the side effects of the two medicines.

2. Verzenio offers benefits to people diagnosed with early-stage, hormone receptor-positive breast cancer, regardless of age.

The latest results from the monarchE trial showed that Verzenio plus hormonal therapy after surgery for early-stage, hormone receptor-positive, HER2-negative breast cancer reduced the risk of recurrence more than hormonal therapy alone, no matter how old a person was. Many past studies didn’t include older people because some women ages 65 and older didn’t want breast cancer treatment. Now, people are living longer, so it’s important to know that medicines work well in adults of all ages. Importantly, the results also showed that when people had to lower the dose of Verzenio because of side effects, the benefit was the same. In other words, a lower dose of Verzenio offered the same reduction in recurrence risk.

3. A meta-analysis showed that ovarian suppression for pre-menopausal women diagnosed with breast cancer leads to better outcomes.

A meta-analysis is a study that combines and analyzes the results of a number of earlier studies. In this case, the results from 25 studies involving 14,999 women published between 1948 and today were analyzed. The results showed that suppression of ovarian function reduces the risk of recurrence and death by about 18%.

4. Taking tamoxifen at night offers more benefits. A study found that taking tamoxifen at night, rather than in the morning, offered better outcomes. The study also found that the time a person takes an aromatase inhibitor doesn’t change outcomes. So if you have the option, why not take tamoxifen at night?

5. Patritumab deruxtecan (HER3-DXd) offered benefits for people diagnosed with metastatic breast cancer. About 60% to 70% of breast cancers express the HER3 protein. Study results showed that HER3-DXd offered benefits — including shrinking the cancer — for a variety of metastatic breast cancers that had grown while being treated with other medicines. Cancer types included hormone receptor-positive, triple-negative, and HER2-low. The most common side effects were nausea, fatigue, diarrhea, and vomiting. Most of the side effects were grade 1 or grade 2, which means they were less severe. HER3-DXd isn’t approved by the U.S. Food and Drug Administration (FDA) yet, but the company that makes it is expected to apply for approval.

6. Diclofenac gel may help ease hand-foot syndrome. Diclofenac gel (brand name: Voltaren), a non-steroidal anti-inflammatory medicine, in a topical gel form seems to help ease hand-foot syndrome caused by the chemotherapy medicine Xeloda (chemical name: capecitabine). Maryam Lustberg, MD, MPH, chief of breast medical oncology at the Yale Cancer Center and president of the Multinational Association of Supportive Care in Cancer, tweeted that it was practice-changing.

— Last updated on July 20, 2023 at 4:02 PM

This information is provided by Breastcancer.org.

Posted in: Medical/Science, Research