PEG-liposomal doxorubicin (PLD) at 40mg/m2 versus 50mg/m2 every month for patients with metastatic breast cancer: A comparative analysis of two prospective phase II studies

Abstract

700 Background: Safety and tolerability are main objectives in the treatment of patients with advanced breast cancer (MBC). In randomized studies, PLD has demonstrated equivalent efficacy and less toxicity compared to doxorubicin. However, specific side effects of PLD at standard doses such as the palmo-plantar erythema (PPE) may severely alter the quality of life in patients with MBC. This study was designed to evaluate a dose modification of PLD (40 mg/m2 every month) in patients with MBC. Methods: Ninety-one previously treated patients with MBC were enrolled to 2 subsequent multicenter phase II studies with identical study design. Patients were treated with PLD 50mg/m2 monthly (n=46) or PLD 40mg/m2 monthly (n=45) and were evaluated weekly for toxicity and monthly for tumor response. Treatment was continued unless progression of disease or unacceptable toxicity was observed. Main selection criteria were: measurable disease; at least 1, maximum 2 pretreatments; age 18 - 80 years; Karnofsky 70%; sufficient hematological and organ function. Results: Patient characteristics, efficacy results and toxicities for the two groups are shown in the table below. Conclusions: Compared to PLD at 50mg/m2, PLD at 40mg/m2 showed less CTC Grade 3/4 PPE, dose reductions, and treatment shifts due to non-hematological toxicity. There were no significant differences in efficacy between the two doses but a tendency toward a prolonged PFS and OS in patients treated with PLD at 50mg/m2. No significant financial relationships to disclose.