Patent ID: 8518897

Claim:
A method of treating a patient having HER-2 positive breast cancer characterized by having elevated levels of HER-2 expression as compared to normal cells of the same type, comprising: providing cells, tissue, or fluid from a patient suspected of having HER-2 positive breast cancer, wherein the provided cells, tissue or fluid are selected to be suitable for testing to characterize HER-2 levels in breast cancer; testing said provided cells, tissue, or fluid for one or more of the gene copy number of HER-2, the amount of HER-2 mRNA, or the amount of HER-2 protein as an indication of the level of HER-2 expression; and if said level is elevated, administering to said patient an pharmaceutically effective amount of an HSP90 inhibitor and a second therapeutic agent different from the HSP90 inhibitor, wherein said HSP90 inhibitor has an IC 50 at least two-fold lower for said provided cells in said patient having elevated Her-2 than for cells that do not have elevated Her-2 and the administered amount is correspondingly lower than the amount that would be required for cells that do not have elevated Her-2, and said second therapeutic agent is an anti-cancer or cytotoxic agent.