Clinical outcome of patients with brain metastases from HER2-positive breast cancer treated with lapatinib and capecitabine

Background: In the present study, we investigated the clinical outcome of patients with brain metastases (BMs) from human epidermal growth factor receptor 2-positive (HER2+) breast cancer (BC) treated with lapatinib and capecitabine (LC). Methods: Of 81 HER2+ metastatic BC patients treated with LC at two Italian institutions, 30 patients with BMs eligible for the analysis were identified. All patients were pretreated with trastuzumab for metastatic disease. No patients had received prior lapatinib and/or capecitabine. Results: Median age was 45 years (range 24-75) and 26 of 30 patients (86.7%) had received prior cranial radiotherapy. In the 22 patients with BMs evaluable for response, 7 partial responses (31.8%) and 6 disease stabilizations (27.3%) were observed. Overall, the median brain-specific progression-free survival was 5.6 months (95% confidence interval 4.4-6.8). Patients treated with LC had a median overall survival (from the time of development of BMs) significantly longer compared with 23 patients treated with trastuzumab-based therapies only beyond brain progression (27.9 months versus 16.7 months, respectively, P = 0.01). Conclusions: LC is active for BMs from HER2+ BC in patients not pretreated with either lapatinib or capecitabine. The introduction of LC after the development of BMs may further improve survival compared with trastuzumab-based therapies only beyond brain progression.