Background: The aim of this study was to evaluate the efficacy of lapatinib combined with capecitabine for patients with HER2 positive metastatic or unresectable locally advanced breast cancer who had previously been treated with anthracyclines, taxanes, and or trastuzumab.
Methods: Forty patients were enrolled. All patients received lapatinib 1250 mg once daily and capecitabine 2000 mg/m2/day, divided into 2 doses, on days 1-14, every 21 days. Tumor response was assessed by RECIST criteria version 1.1. Progression free survival (PFS) and overall survival (OS) were assessed using Kaplan- Meier method.
Results: Median age was (46 years), ranging (27-75). Four patients (10%) achieved complete response, 12 (30%) partial response, and 13 (32.5%) stable disease (SD). Overall response rate (ORR) was 40%. Clinical benefit rate (ORR+SD) was 72.5%. The median PFS was 12 months. Median OS was 22.6 months. Restricted performance status and three or more metastatic sites had significant impact on the OS and PFS. The protocol was well tolerated with manageable toxicity. Grade three hand and foot syndrome was observed in three cases and it was improved after reduction of capecitabine dose. Grade three neutropenia was detected in one case and was resolved with proper management.
Conclusion: The combination of lapatinib and capecitabine is relatively effective and well tolerated in improving PFS and OS in female patients with advanced and metastatic breast cancer after failure of other chemotherapeutic agents as anthracyclins, taxanes and trastuzumab.