Promising Novel Approaches for Metastatic HER2-Overexpressing Breast Cancer Progressing on Trastuzumab: (1) Pertuzumab+Trastuzumab Active after Failed Sequential Therapy; (2) Adding Lapatinib & Continuing Trastuzumab Better than Lapatinib Alone, Reinforcing Trastuzumab Use Beyond Progression; (3) Trastuzumab+Ridaforolimus Effective in Heavily Pretreated Patients; (4) T-DM1 Shrinks Tumors after Multiple Previous Treatments.PDF下载