Multicenter Experience of Nonpegylated Liposomal Doxorubicin Use in the Management of Metastatic Breast Cancer

BACKGROUND: This study aimed to investigate the use of nonpegylated liposomal doxorubicin (NPLD) in the management of metastatic breast cancer (MBC) within routine UK clinical practice and to assess its efficacy and tolerability. PATIENTS AND METHODS: All patients that received NPLD for MBC at 5 institutions were identified. Clinicopathologic details, echocardiographic data, and toxicities were documented. Response to treatment, outcome, cardiotoxicity, and safety were assessed. RESULTS: 63 patients (median age at NPLD therapy, 53.5 years) who had received NPLD were identified; 18 (29%) were anthracycline-naïve, and 42 (67%) were anthracycline-pretreated (median cumulative dose of epirubicin, 450 mg/m(2)). In 3 cases, prior treatment history was not available. NPLD was most frequently (16 [25%] of 63 patients) administered as first-line chemotherapy (median, third-line; range, 1-9), although it was given later in anthracycline-pretreated patients (median, fourth-line; range, 1-9). Overall, 14 (29%) of 49 evaluable patients achieved an objective response, which increased to 10 (71%) of 14 when NPLD was given first-line (anthracycline-naïve, 8 [100%] of 8; anthracycline-pretreated, 2 [50%] of 4; adjuvant treatment unknown, 2). Median progression-free survival was 7 months (first-line, 18 months, vs. ≥ second-line, 6 months; P = .0066), and median overall survival was 10 months (first-line, 18 months, vs. ≥ second-line, 10 months; P = .0971). Toxicities tended to be grade 1 or 2. Three patients had cardiotoxicity (left ventricular ejection fraction < 50% or a fall of ≥ 10% from baseline), which resolved during treatment. CONCLUSION: NPLD was used in both anthracycline-naïve patients and those with prior exposure. There is evidence of clinical activity in those with prior exposure to anthracyclines, with a low incidence of cardiotoxicity.