Purpose: Anthracyclines and fluoropyrimidines are very active in breast cancer, while liposomal doxorubicin has low cardiotoxicity. We conducted a dose-finding study of the combination of liposomal doxorubicin and capecitabine in patients with pretreated metastatic breast cancer.
Patients and methods: Patients received liposomal doxorubicin 60 mg/m2 on day 1 plus capecitabine 825 mg/m2 bid (level 0) or 1,000 mg/m2 bid (level 1) on days 1-14 of each 21-day cycle to establish the maximum tolerated dose (MTD) and cardiac safety.
Results: Nine patients were enrolled and a total of 52 courses were delivered (median 6 cycles per patient [range 4-7]). Grade 4 neutropenia occurred in 15% of cycles, with one episode of febrile neutropenia; most nonhematological toxicities were mild or moderate. No formal MTD was established, and the study was closed because two cardiac events were observed at dose level 1 and another at dose level 0 in patients pretreated with epirubicin > or = 560 mg/m2.
Conclusions: The recommended dose for phase II studies is liposomal doxorubicin 60 mg/m2 on day 1 plus capecitabine 825 mg/m2/bid on days 1-14 of each 21-day cycle. Despite the lower cardiotoxicity of liposomal doxorubicin, the risk of cardiac damage persists in anthracycline-pretreated individuals and mandates close cardiac monitoring and careful evaluation of the overall cumulative dose.