Supplementary Materials for "Prognostic Significance of ctDNA Mutations in HER2-Targeted Breast Cancer Therapy: A Meta-analysis"

Supplementary Table 1. Summary of included studies evaluating the prognostic value of ctDNA mutation status in HER2-targeted therapy for breast cancer. This table summarizes the key characteristics of the 12 included studies investigating the association between ctDNA mutation status and PFS in patients receiving anti-HER2 therapies. Data include publication year, country, study type, clinical phase, treatment regimens, ctDNA mutation frequency, and HR comparing PFS between MT and WT ctDNA groups.Abbreviations:ctDNA, circulating tumor DNA; PFS, progression-free survival; HR, hazard ratio; CI, confidence interval; WT, wild type; MT, mutant type; RCT, randomized controlled trial; N/A, not available; Y, yes; N, no.*Note: Median PFS values are reported in months. Where available, HRs and 95% confidence intervals were extracted directly from the original publications. All HRs calculated with wild-type as reference; HR>1 indicates worse prognosis in mutation group. Studies varied in anti-HER2 regimens, including monoclonal antibodies, TKIs, and ADCs, as well as combination with chemotherapy or endocrine therapy. Supplementary Figure 1. Sensitivity analysis of ERBB2 subgroup.Supplementary Figure 2. Funnel plot of ERBB2 subgroup. Supplementary Figure 3. Sensitivity analysis of PIK3CA subgroup.Supplementary Figure 4. Funnel plot of PIK3CA subgroup. Supplementary Figure 5. Sensitivity analysis of the TKI subgroup.Supplementary Figure 6. Funnel plot of the TKI subgroup. Supplementary Figure 7. Sensitivity analysis of the non-TKI subgroup.Supplementary Figure 8. Funnel plot of the non-TKI subgroup. Supplementary Figure 9. Sensitivity analysis of the pyrotinib subgroup.Supplementary Figure 10. Funnel plot of the pyrotinib subgroup. Supplementary Figure 11. Sensitivity analysis of the non-pyrotinib subgroup.Supplementary Figure 12. Funnel plot of the non-pyrotinib subgroup. Supplementary Figure 13. Sensitivity analysis of monotherapy subgroup.Supplementary Figure 14. Funnel plot of monotherapy subgroup. Supplementary Figure 15. Sensitivity analysis of combination subgroup.Supplementary Figure 16. Funnel plot of combination subgroup. Supplementary Figure 17. Sensitivity analysis of capecitabine-based subgroup.Supplementary Figure 18. Funnel plot of capecitabine-based subgroup. Supplementary Figure 19. Sensitivity analysis of other combination subgroup.Supplementary Figure 20. Funnel plot of other combination subgroup.