Objectives: The aim of this study was to evaluate the importance of growth-differentiation factor-15 (GDF-15) levels and tissue Doppler imaging (TDI) in the early detection of anthracyclineinduced cardiomyopathy during the treatment of childhood cancers. Patients and Methods: Twenty patients (13 males and 7 females) newly diagnosed with childhood cancer whose treatment protocol included anthracycline were included in the study. Echocardiography, including M-mode, pulse Doppler, and TDI, was performed after the first anthracycline treatment at cumulative doses of 100, 200, and 300 mg/m2 and at least 6 months after the last treatment. GDF-15 and troponin-I were also measured at these time points. Results: The median age of the patients was 14 years (range, 3 to 18 y). The median cumulative anthracycline dose was 220 mg/m2 (range, 60 to 400 mg/m2). Conventional pulse wave and pulse wave tissue Doppler methods revealed significant differences in the right ventricular myocardial performance indices of the patients who received cumulative anthracycline doses of 300 mg/m2 compared with their indices at least 6 months after the last treatment. The serum GDF-15 levels after the cumulative anthracycline dose of 200 mg/m2 were also higher than the patients' pretreatment levels. Conclusions: Doppler/TDI and GDF-15 levels may be used in the early determination of anthracycline-induced cardiomyopathy during the treatment of childhood cancers.