When is tarceva (erlotinib) indicated?

Cancer: Specifically lung cancer, but perhaps others, in which a specific mutation is present. For now it is only used for people with metastatic lung cancer, but some other forms of cancer in which specific activating egfr mutations are present. For those with the proper activating mutations, it is very effective, but the response typically does not last. Tumors evolve the means to adapt to the drug.