Efficacy of lapatinib combined with capecitabine in patients with HER2‑positive metastatic breast cancer in a real‑world study

The aim of the present study was to determine the efficacy and safety of lapatinib-based treatment for patients with human epidermal growth factor receptor-2-positive (HER2+) metastatic breast cancer (MBC). The aim of the present real-world study was to investigate the medical records and follow-up information of 92 patients with HER2+ MBC who received a lapatinib-based regimen at the recurrent/metastatic stage, 78 of whom had been pretreated with trastuzumab. The results demonstrated that the median progression-free survival (PFS) was 5.8 months and the overall survival (OS) was 21.5 months, with an objective response rate (ORR) of 21.7%, disease control rate (DCR) of 87.0% and clinical benefit rate (CBR) of 47.8%. In the patients receiving a lapatinib-based regimen as first-, second- and third/later-line treatment, the median PFS was 10.4, 5.2 and 5.1 months (P=0.048), the median OS was 32.9, 29.1 and 13.0 months (P<0.001), the ORR was 38.9, 23.3 and 13.60%, and the DCR was 100, 83.3 and 84.1%, respectively. In the trastuzumab-resistant (n=71) and trastuzumab-sensitive (n=21) patients, the median PFS was 5.2 and 9.1 months (P=0.032), and the median OS was 21.4 and 44.3 months (P=0.003), respectively. In the patients who received lapatinib plus chemotherapy (n=68), the median PFS with lapatinib plus capecitabine (n=38) was 8.1 months, as compared with the 5.1 months with lapatinib plus other chemotherapy agents (n=30; P=0.005). The median PFS of 14 patients with brain metastases was 8.4 months, with an ORR of 35.7% and a DCR of 85.7%. Multivariate analysis revealed that the line of lapatinib-based treatment and its combination with capecitabine or a different agent were independent prognostic factors for the median PFS in patients with HER2+ MBC. A limited number of adverse events were observed with the combination of lapatinib and capecitabine. Therefore, the findings of the present study suggested that lapatinib-based treatment is effective in patients with HER2+ MBC (even in trastuzumab-pretreated patients), and the combination of lapatinib with capecitabine may be recommended due to its good efficacy, convenience and tolerability.