Treatment Outcomes of HER-2 Positive Metastatic Breast Cancer Patients Treated with Pertuzumab in the First Line Setting- Real Life Experience

Abstract

INTRODUCTION: Pertuzumab is a new recombinant humanized monoclonal antibody, has been developed to inhibit the formation of HER2: HER3 heterodimerization. The clinical benefit of pertuzumab therapy in HER2 positive metastatic Breast Cancer (mBC) patients in the first-line setting has been shown in previous phase III studies. Herein we aimed to analyze the efficacy and toxicity profile of pertuzumab in patients with HER2 positive mBC. METHODS: This was a retrospective study of 28 patients with mBC followed from two different centers in Turkey. All patients were treated with pertuzumab in the first line setting, with combination of trastuzumab and docetaxel. Treatment outcomes along with drug efficacy and safety were retrospectively analyzed. RESULTS: At a median follow-up time of 10.1 (2.4-25.2) months, among the 28 patients, 1 (3.6%) died and 2 (7.1%) developed disease progression. The median age of study population was 47 (18-74) years. Excluding 1 patient, all had (96.4%) de-novo metastatic disease at presentation. The median number of treatment cycles was 7 (4 - 12) for docetaxel, 18 (4 - 35) for pertuzumab + trastuzumab, and 10 (1 - 29) for the maintenance therapy (pertuzumab + trastuzumab). The most common side effects were; fatigue (75%) and arthralgia/myalgia (64.3%). Grade 3 or 4 toxicity were observed to be very infrequent. DISCUSSION AND CONCLUSION: Even with a small sample size, our results confirm that, pertuzumab, trastuzumab and docetaxel combination therapy in the first line setting in HER2 positive mBC patients is the standardof care, with acceptable toxicity profile and promising survival results.

Keywords

• metastatic breast cancer
• her2 positive
• pertuzumab
• progression free survival
• overall survival
• toxicity