Neoadjuvant immunotherapy in breast cancer: a paradigm shift?

Area of Science:

• Oncology
• Immunotherapy
• Breast Cancer Research

Background:

• Early-stage triple-negative breast cancer (TNBC) has a significant recurrence rate despite local treatment.
• Neoadjuvant systemic therapy is increasingly used to improve outcomes in TNBC and other breast cancers.
• Immunotherapy, specifically PD-1/PD-L1 inhibitors, is being investigated in neoadjuvant settings for breast cancer.

Purpose of the Study:

• To review current literature on neoadjuvant clinical trials evaluating immunotherapy in breast cancer.
• To highlight the efficacy of PD-1/PD-L1 inhibitors combined with chemotherapy in early-stage TNBC.
• To emphasize the need for predictive biomarkers to optimize immunotherapy selection and minimize toxicity.

Main Methods:

• Review of prospective phase III randomized trials and ongoing clinical trials.
• Analysis of data from trials assessing neoadjuvant chemotherapy with PD-1/PD-L1 inhibitors versus placebo.
• Focus on pathologic complete response (pCR) rates as a primary endpoint.

Main Results:

• Pembrolizumab combined with neoadjuvant chemotherapy significantly increased pCR rates in early-stage TNBC.
• Atezolizumab with neoadjuvant chemotherapy also improved pCR rates in early-stage TNBC, irrespective of PD-L1 status.
• Ongoing trials are exploring other PD-1/PD-L1 inhibitors in various breast cancer subtypes.

Conclusions:

• Neoadjuvant immunotherapy demonstrates promise in enhancing treatment response for early-stage TNBC.
• Patient selection is crucial due to variable benefit and potential adverse events associated with immunotherapy.
• Further research is needed to identify biomarkers that predict response to neoadjuvant immunotherapy in breast cancer.