Preliminary results of whole brain radiotherapy with concurrent trastuzumab for treatment of brain metastases in breast cancer patients.

Abstract

To assess the use of trastuzumab concurrently with whole brain radiotherapy (WBRT) for patients with brain metastases from human epidermal growth factor receptor-2-positive breast cancer. Between April 2001 and April 2007, 31 patients with brain metastases from human epidermal growth factor receptor-2-positive breast cancer were referred for WBRT with concurrent trastuzumab. At brain progression, the median age was 55 years (range, 38-73), and all patients had a performance status of 0-2. The patients received trastuzumab 2 mg/kg weekly (n = 17) or 6 mg/kg repeated every 21 days (n = 14). In 26 patients, concurrent WBRT delivered 30 Gy in 10 daily fractions. In 6 patients, other fractionations were chosen because of either poor performance status or patient convenience. After WBRT, radiologic responses were observed in 23 patients (74.2%), including 6 (19.4%) with a complete radiologic response and 17 (54.8%) with a partial radiologic response. Clinical responses were observed in 27 patients (87.1%). The median survival time from the start of WBRT was 18 months (range, 2-65). The median interval to brain progression was 10.5 months (range, 2-27). No Grade 2 or greater acute toxicity was observed. The low toxicity of trastuzumab concurrently with WBRT should probably not justify delays. Although promising, these preliminary data warrant additional validation of trastuzumab as a potential radiosensitizer for WBRT in brain metastases from breast cancer in the setting of a clinical trial.