The secondary aim of the study is to estimate the proportion of patients with decreased (evaluation j - evaluation j+1) peak longitudinal systolic strain (ε) or strain rate (SR), peak radial systolic ε or SR, peak radial systolic myocardial velocity or peak longitudinal systolic myocardial velocity among those who have a shortening fraction (SF) ≥ 29% prior to each infusion of anthracycline. This study will evaluate whether the serum levels of cTn-T and/or NT-BNP will increase following doxorubicin administration. The study will evaluate whether the serum levels of cTn-T and/or NT-BNP will increase with increasing cumulative doxorubicin dose.