Lapatinib-based therapy in heavily pretreated HER2-positive metastatic breast cancer: a single institution experience.

Aims and background. Lapatinib in combination with capecitabine is feasible in patients with HER2-positive metastatic breast cancer pretreated with anthracyclines, taxanes and trastuzumab, but inferior results were reported in the global lapatinib expanded access program in comparison with the phase III registration trial. Methods. and study design. Women with HER2-positive metastatic breast carcinoma after antracycline, taxane and trastuzumab-based regimens were treated at progression with lapatinib plus capecitabine. The outcome of these patients was evaluated. From April 2007 to August 2010, 68 patients were treated overall. Results. Median progression-free survival was 6 months (range, 1-29), and median overall survival was 26 months (range, 1-39). Eight (12%; 95% CI, 4-25) patients experienced a complete response. Partial response was observed in 22 patients (31%; 95% CI, 20-42), for an overall response rate of 43% (95% CI, 31-55). The treatment with lapatinib plus capecitabine was well tolerated, with grade 3-4 toxicity reported in few patients, and no treatment-related deaths were noted. Of note, no cardiac toxicity was reported in this highly pretreated group of patients or in the subgroup of 10 elderly patients. Conclusions. Our data confirm that lapatinib plus capecitabine is an active regimen even in heavily pretreated patients with visceral and brain metastases and is feasible and active also in selected elderly patients.