Substituting doxorubicin with nonpegylated liposomal doxorubicin (NPLD) in adjuvant/primary chemotherapy for early breast cancer, impact in cardiac function: A pilot study.

Abstract

616 Background: NPLD (Myocet, Cephalon UK Ltd) is effective for the treatment of metastatic breast cancer and is less cardiotoxic than doxorubicin. However, there are currently limited data for NPLD in early breast cancer, where it may be particularly beneficial, as cardiotoxicity may be treatment-limiting and is a key survivorship issue. Methods: Consecutive patients with early breast cancer treated with NPLD substituting for doxorubicin were studied to evaluate change in cardiac function. Echocardiogram results and details of other treatments and disease progression were assessed. Results: 80 patients (median age 54 (33-77) years) were studied, with most receiving NPLD adjuvantly (76%; primary 24%) in sequence with a taxane (AC+T 73%; AC 8%; TAC 19%). 83% had radiotherapy and 16% received trastuzumab. The 48 evaluable patients had mean left ventricular ejection fraction (LVEF) values within the normal range (>50%) at baseline (64%), during chemotherapy (65%), < 4 months (63%) and >12 months (63%) after chemotherapy. There was no significant change in cardiac function whether NPLD was given as primary or adjuvant therapy, at baseline (65% vs. 64%), during (65% vs. 65%) or < 4 months after therapy (60% vs. 64%). No difference in cardiac function was observed when categorised by chemotherapy regimen at baseline (AC: 63%; AC+T: 63%; TAC: 67%), during (AC: 64%; AC+T: 65%; TAC: 67%) or < 4 after therapy (AC: no data; AC+T: 63%; TAC: 63%). There was also no difference in cardiac function between patients who did and did not receive trastuzumab at baseline (65% vs. 64%), during (64% vs. 66%), or < 4 months after therapy (65% vs. 62%). Results for age > 60 vs. < 60 years were also similar (baseline 67% vs. 63%; during 67% vs. 65%; or < 4 months after 64% vs. 63%). 8 (10%) of the 80 patients experienced disease recurrence/progression and 2 (3%) died. Conclusions: NPLD appears to have good cardiac tolerability and be efficacious in early breast cancer. Larger, longer-term studies are required to confirm these promising results to protect cardiac function, particularly when breast cancer patients are living longer with multiple lines of treatment for metastatic cancer. No significant financial relationships to disclose.