Safety and efficacy of metronomic non-pegylated liposomal encapsulated doxorubicin in heavily pretreated advanced breast cancer patients

Metronomic administration of the same chemotherapy agents (lower doses with closer intervals) may optimize their antiangiogenic properties. The aim of our study was to determine the efficacy and safety of a metronomic regimen based in non-pegylated liposomal doxorubicin (NPLD) in advanced breast cancer patients. Clinical records of patients with pretreated advanced breast cancer and who were treated with the Metronomic-Cooper-type regimen consisting of weekly fixed doses of NPLD (30 mg IV) plus 5-Fluorouracil (5-FU) (500 mg IV) plus vincristine (0.25 mg IV) and daily oral cyclophosphamide (50 mg) plus prednisone (20 mg) were reviewed. In 84 pretreated patients, a tumor response was observed in 38 patients (45 %); stable disease was observed in 23 patients (27 %). Median progression-free survival (PFS) time to progression was 8.4 months and median overall survival (OS) was 21 months. The most common grade 2-3 hematologic adverse event was neutropenia, which was observed in 47 patients (56 %). Febrile neutropenia was observed in 10 patients (12 %). The most common non-hematologic adverse events were asthenia and mucositis which were observed in 60 patients (71 %) and 26 patients (31 %), respectively. Three patients (4 %) experienced an asymptomatic decline of the left ventricular ejection fraction. NPLD-based metronomic regimen was effective and safe in pretreated advanced breast cancer patients. It could be considered as an appealing option to treat patients previously exposed to anthracyclines.