Meta-analysis of the clinical efficacy and safety of T-DM1 in the treatment of HER2-positive breast cancer

This meta-analysis aims to comprehensively evaluate the efficacy and safety of T-DM1 in treating HER2-positive breast cancer, providing insights for clinical practice. We conducted a literature search in PubMed, Cochrane Library, and Embase databases up to September 2023, collecting randomized controlled trials and cohort studies on T-DM1 for HER2-positive breast cancer. Out of 316 initially retrieved articles, 12 studies meeting the quality and inclusion criteria were included after a rigorous screening process. We used RevMan 5.3 software for the meta-analysis, employing fixed or random-effect models. Odds ratios (RRs) and 95% confidence intervals (CIs) were calculated as effect size measures. We conducted sensitivity analyses and assessed publication bias to ensure the results’ stability and reliability. In seven studies, T-DM1 treatment significantly prolonged OS in patients with HER2-positive breast cancer [hazard ratio (HR) = 0.70, 95% CI: 0.64–0.77, P < 0.01], and the effect was especially pronounced in patients with advanced disease (HR = 0.64, 95% CI: 0.54–0.76, P < 0.001). Analysis of pCR rates did not show a significant difference (OR = 0.91, 95% CI: 0.48–1.73, P = 0.77). In five studies, ORR improved, but the difference between the two groups was not significant (OR = 1.16, 95% CI: 0.66–2.05, P = 0.61). Analysis of progression-free survival (PFS) showed a significant improvement in the experimental group relative to the control group (HR = 0.69, 95% CI: 0.57–0.84, P = 0.0003). Regarding the incidence of total adverse events, no significant difference was seen between the two groups (OR = 2.16, 95% CI: 0.98–4.79, P = 0.06), but for specific adverse events, such as leukopenia and neutropenia, the T-DM1 group demonstrated a significant reduction relative to the other treatment regimens. The results underscore the potential of T-DM1 in enhancing survival among patients with advanced HER2-positive breast cancer, yet they also highlight variability in effectiveness concerning pCR rate and ORR. The findings on adverse effects underscore the necessity of a balanced consideration of T-DM1’s risks and benefits. Future research should focus on a more detailed examination of responses in varied patient populations, long-term outcomes, and a thorough economic evaluation of T-DM1, along with an exploration into treatment resistance. This will provide a more nuanced understanding of T-DM1’s role in the treatment landscape of HER2-positive breast cancer.