PURPOSE: One of the great conundrums for both oncologists and cardiologists is how to best monitor the potential and actual cardiotoxicity of doxorubicin. Pegylated-liposomal doxorubicin (PLD) has a safer cardiotoxicity profile than bolus administration of doxorubicin. Although ejection fraction (EF) is commonly performed to monitor doxorubicin-induced cardiotoxicity, evidence for its predictive utility is limited. We examined the incidence of doxorubicin-induced heart failure (HF) in patients who received a large cumulative dose of doxorubicin as PLD and its relation to EF and HF. METHODS: A retrospective chart review of patients who received a large cumulative dose of PLD, sometimes after previous free doxorubicin treatment, was performed to examine the incidence of doxorubicin-induced heart failure (HF) and its relation to EF and development of HF. RESULTS: No definite doxorubicin-induced clinical HF was observed among 56 patients (median age 54; 15-93) who received a cumulative doxorubicin dose (free + PLD) of >450 mg/m. Of these, 49 received >500 mg/m, 28 > 700 mg/m, 19 > 800 mg/m, 14 > 1000 mg/m, and 5 > 1400 mg/m. The EF varied greatly over time in some patients treated with PLD in the absence of symptoms or signs of heart failure, and was not particularly useful in making decisions regarding further dosing. CONCLUSIONS: Pegylated-liposomal doxorubicin was associated with a low risk of doxorubicin-induced HF in a retrospective cohort of patients receiving large cumulative doses of doxorubicin and long-term follow-up. EF did not predict doxorubicin-induced cardiotoxicity in our cohort of adult patients receiving PLD. Given the lack of prognostic clarity regarding modest EF changes, regular EF monitoring may not be warranted, at least when PLD is used in adults. Modest changes in EF should probably not be used to limit a patient's access to PLD, but may warrant cardiology consultation for long-term follow-up after completion of therapy.