Is Paclitaxel Less Cardiotoxic in the Treatment of Breast Cancer Before or After Doxorubicin?

Background: The combination of doxorubicin (DOX) with paclitaxel (PTX) effectively treats breast cancer (BC). However,DOX-associated cardiotoxicity (CTX) is aggravated by the use PTX. Consensus lacking about which drug sequence involves most CTX. Objectives: To evaluate whether DOX followed PXT or reverse has greatest cardiotoxic potential in treatment BC. Methods: Prospective study women primary BC who received four cycles and 12 infusions Participants were divided into Group 1 (G1; before DOX) 2 (G2; PXT) at discretion oncologist. CTX was defined as an absolute reduction left ventricular ejection fraction (LVEF) > 10% to a value <53%. Patients underwent clinical evaluations echocardiography (Phase 1) one year after 2). Results: Sixty-nine evaluated: 19 G1 50 G2. groups had similar characteristics. doses radiation, DOX, PTX used similar. Eight (11.6%) patients developed CTX: two (10.5%) six (12.0%) G2 (p=0.62). mean LVEF between Phase (G1=65.1±3.5%; G2=65.2±3.9%; p=0.96), significant noted both groups: G1=61.4±8.1% (p=0.021) G2=60.8±7.6% (p<0.001). Although lower, remained (p=0.79). Conclusions: In chemotherapy, incidence end first regardless