在乳腺癌的疾病分型中，HER-2阳性乳腺癌是指在一些乳腺癌中，HER2基因扩增或受体过表达，导致癌细胞的快速生长。这类乳腺癌ER-/PR-/HER2+，且Ki-67高表达，通常恶性程度高，患者易出现腋窝淋巴结转移情况。

Caption Researchers found in the lab that lapatinib causes HER2 and HER3 to form pairs on cell membranes, priming them in an inactive state (left) so that when growth factors are present, they ...