The Effectiveness of Lapatinib in HER2-Positive Metastatic Breast Cancer Patients Pretreated With Multiline Anti-HER2 Treatment: A Retrospective Study in China.

Our findings suggest that patients would benefit more from trastuzumab plus lapatinib than from lapatinib or trastuzumab alone for second line treatment in the advanced stages of the disease. Lapatinib could be used as an alternative selection for HER2-positive metastasic breast cancer patients when there is disease progression after trastuzumab or pyrotinib treatment, which is used as part of China's national health insurance.