Benefits and adverse events of combined chemotherapy and immune checkpoint inhibition in non-metastatic triple-negative breast cancer: a systematic review and an updated meta-analysis
Year: 2026
Type: review
Study designs: Systematic Review, Meta-Analysis
Abstract: Background: Previous studies have reported inconsistent findings regarding the efficacy and safety of chemotherapy combined with immune checkpoint inhibitors in patients with non-metastatic triple-negative breast cancer (TNBC). This meta-analysis was designed to assess the clinical benefits and tolerability associated with chemoimmunotherapy in non-metastatic TNBC. Methods: We conducted a comprehensive search in PubMed, Web of Science, Embase, and the Cochrane Library. The main endpoint is pathological complete response (pCR) rate, with other endpoints of event-free survival (EFS), disease-free survival (DFS) and invasive DFS (iDFS), overall survival (OS), and treatment-related adverse events (AEs). Results: Data for the meta-analysis came from 8 randomized controlled trials (RCTs). Combining immune checkpoint inhibitors (ICIs) with chemo, they were more effective than chemo in achieving a pCR [odds ratio (OR) =1.82, 95% confidence interval (CI): 1.37-2.41; P<0.001]. The benefit was more pronounced in the group of patients whose lymph nodes were positive (OR =2.19, 95% CI: 1.62-2.96; P<0.001). Regarding OS data, we observed improved EFS with ICI-based regimens [hazard ratio (HR) =0.73, 95% CI: 0.61-0.88; P<0.001]. Although the results of neoadjuvant chemotherapy were found to be statistically significant for iDFS and OS, the adjuvant setting did not demonstrate a similar benefit, and DFS was modestly improved. Safety outcomes showed ≥ Grade 3 AEs were more frequent in the treatment group [relative risk (RR) =1.13, 95% CI: 1.04-1.22; P=0.003], and serious AEs (SAEs) (RR =1.70, 95% CI: 1.49-1.94, P<0.001) among the combination therapy cohorts. The programmed cell death protein 1 (PD-1) inhibitors had more immune-related AEs (irAEs) than the PD-1 ligand (PD-L1) inhibitors. The majority of AEs were controllable in clinical settings, with no additional SAEs being reported. Conclusions: Combination therapy with ICIs and chemo improves pCR in patients with early-stage or loco-regional TNBC, and may provide better survival benefit.
Authors: Jianmin Wu, Kejing Zhang
Language: English
Subfield: Cancer Research
Domain: Life Sciences
Open Access status: hybrid
OpenAlex ID: W7223106334