Galectin-9, FABP4 and pentraxin-3 are associated with myocardial dysfunction and discriminate chemotherapy-related cardiac dysfunction in anthracycline-treated breast cancer: a single-centre retrospective study.

BACKGROUND: Anthracycline-based chemotherapy improves breast cancer outcomes but may cause cancer therapy-related cardiac dysfunction (CTRCD). Biomarkers reflecting inflammatory and metabolic myocardial stress may complement imaging surveillance, but the combined value of galectin-9 (Gal-9), fatty-acid-binding protein 4 (FABP4) and pentraxin-3 (PTX-3) is unclear. OBJECTIVE: This study aimed to evaluate whether serum Gal-9, FABP4 and PTX-3 are associated with myocardial dysfunction and discriminate CTRCD. METHODS: This single-centre retrospective cohort included 219 women receiving at least three anthracycline-based cycles from December 2022 to June 2025. Patients were classified as CTRCD (n = 66) or non-CTRCD (n = 153) using ASE/EACVI and ESC criteria. Baseline and post-cycle-3 echocardiography and hs-cTnI were recorded; post-cycle-3 biomarkers were measured by ELISA. Analyses included adjusted correlations, multivariable logistic regression, ROC/DeLong testing and bootstrap validation. RESULTS: Baseline characteristics were comparable. After chemotherapy, Gal-9, FABP4 and PTX-3 were higher, whereas LVEF, |GLS| and MCI were lower, in the CTRCD group (all P < 0.05). Biomarkers correlated inversely with LVEF, |GLS| and MCI after adjustment (all P < 0.001). The combined biomarker score was independently associated with CTRCD (adjusted OR 3.25 per SD; 95% CI 2.09-5.07; P < 0.001). The combined model achieved an AUC of 0.880 (95% CI 0.829-0.920), optimism-corrected AUC of 0.854 and cross-validated AUC of 0.846, improving the clinical-model AUC from 0.642 to 0.872 (P < 0.001). CONCLUSION: Gal-9, FABP4 and PTX-3 were associated with concurrent myocardial dysfunction and improved discrimination of on-treatment CTRCD. This candidate adjunctive panel requires serial sampling and external validation before clinical use.