What Did the Research Discover?
This study examined whether adding pembrolizumab (Keytruda), an immune checkpoint inhibitor, to standard chemotherapy before surgery could improve outcomes for patients with early-stage triple-negative breast cancer (TNBC).
In this large phase 3 trial, 1,174 patients with stage II or III TNBC were randomly assigned to receive either:
- Pembrolizumab plus chemotherapy, or
- A placebo plus chemotherapy
The main goal was to see how many patients had a pathological complete response (pCR)—meaning no remaining invasive cancer in the breast or lymph nodes—by the time of surgery.
The results showed that 64.8% of patients who received pembrolizumab with chemotherapy had a pCR, compared to 51.2% of those who received only chemotherapy. This means adding pembrolizumab increased the pCR rate by about 13.6 percentage points, a statistically significant improvement.
Additionally, after about 15.5 months of follow-up, patients who received pembrolizumab were less likely to experience disease progression, recurrence, or death compared to those in the placebo group (7.4% vs. 11.8%).
How Can I Apply This Information?
This study suggests that adding pembrolizumab to chemotherapy may significantly improve treatment response in early-stage TNBC. For patients diagnosed with this aggressive form of breast cancer, this combination therapy could:
- Increase the chance of eliminating cancer before surgery
- Potentially improve long-term survival
However, side effects were slightly more common in the pembrolizumab group. The most frequent severe side effects included low blood cell counts (neutropenia, anemia), fever, and infusion-related reactions. While these are expected with chemotherapy, patients should discuss potential risks and benefits with their doctors to determine if this approach is suitable for them.
If you or a loved one has been diagnosed with early-stage triple-negative breast cancer, this research highlights an important new treatment option that may improve outcomes.
Source:
Schmid P, Cortes J, Pusztai L, McArthur H, Kümmel S, Bergh J, Denkert C, Park YH, Hui R, Harbeck N, Takahashi M. Pembrolizumab for early triple-negative breast cancer. New England Journal of Medicine. 2020 Feb 27;382(9):810-21. https://www.nejm.org/doi/10.1056/NEJMoa1910549?url_ver=Z39.88-2003&rfr_id=ori:rid:crossref.org&rfr_dat=cr_pub%20%200pubmed
