ERBB2 and breast carcinoma: Although the observed population was heavily pretreated, the evaluated regimen was notably effective in terms of response rate, time to progression and survival, with very mild toxicity.These data suggest that in over expressing HER2 metastatic breast cancer patients, sequential trastuzumab based chemotherapeutic regimens can achieve good response rate with prolonged TTP in responding patients, even after other target therapy such as lapatinib based combinations.