Supplementary Materials for "Prognostic significance of ctDNA mutations in advanced HER2-positive breast cancer treated with targeted 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 Fig. 1. Leave-one-out sensitivity analysis for the overall progression-free survival (PFS) meta-analysis. Supplementary Fig. 2. Funnel plot for publication bias in the overall PFS meta-analysis. Supplementary Fig. 3. Sensitivity analysis of ERBB2 subgroup. Supplementary Fig. 4. Funnel plot of ERBB2 subgroup. Supplementary Fig. 5. Sensitivity analysis of PIK3CA subgroup. Supplementary Fig. 6. Funnel plot of PIK3CA subgroup. Supplementary Fig. 7. Sensitivity analysis of the TKI subgroup. Supplementary Fig. 8. Funnel plot of the TKI subgroup. Supplementary Fig. 9. Sensitivity analysis of the non-TKI subgroup. Supplementary Fig. 10. Funnel plot of the non-TKI subgroup. Supplementary Fig. 11. Sensitivity analysis of the pyrotinib subgroup. Supplementary Fig. 12. Funnel plot of the pyrotinib subgroup. Supplementary Fig. 13. Sensitivity analysis of the non-pyrotinib subgroup. Supplementary Fig. 14. Funnel plot of the non-pyrotinib subgroup. Supplementary Fig. 15. Sensitivity analysis of monotherapy subgroup. Supplementary Fig. 16. Funnel plot of monotherapy subgroup. Supplementary Fig. 17. Sensitivity analysis of combination subgroup. Supplementary Fig. 18. Funnel plot of combination subgroup. Supplementary Fig. 19. Sensitivity analysis of capecitabine-based subgroup. Supplementary Fig. 20. Funnel plot of capecitabine-based subgroup. Supplementary Fig. 21. Sensitivity analysis of other combination subgroup. Supplementary Fig. 22. Funnel plot of other combination subgroup.