All AEs will be included in the data listings, including onset timing (timing relative to study treatment administration), duration, severity, relationship, and resolution. The incidence and frequency of treatment-emergent: AEs, SAEs, severe AEs, AEs related to study drug (See Appendix N for causality assessment guidelines) , and AEs which lead to study discontinuation will be presented by treatment group. The incidence and frequency of treatment-emergent AEs will be summarized by treatment group using counts and percentages: • by system organ class and preferred term • by system organ class, preferred term, and maximum severity • by system organ class, preferred term, and strongest relationship to study drug. For the incidence, if a subject experiences the same event more than once, the event with the highest severity will be included in the severity tabulation, and the event with the highest relationship will be included in the relationship tabulation. For the frequency, all AEs will be tabulated. A 2-sided Fisher Exact test will be used to compare the incidence of any expected AEs between the 2 treatment groups. Adverse events origination will be attributed to prior breast cancer therapy, study therapy, or surgery or shared as most appropriate. The results will be tabulated be treatment group. Kaplan-Meier life tables will be used to compare the time to onset and the duration of any AE with >10% incidence. A singly ordered Kruskal-Wallis test will be used to compare the total number of AEs, SAEs, and related AEs per treatment group. The incidence of clinically significant CHF will be estimated for patients in pre-specified treatment groups. Symptomatic CHF is defined as the occurrence of objective findings on clinical examination (e.g., rales, S3, elevated jugular venous pressure) and confirmed by chest X-ray and either MUGA or ECHO. Difference in risk based on prior anthracycline exposure as well as risk factors such as ECHO performance status and smoking status will be explored.