Serum is collected after failure of first-line therapy for proteomic analysis by matrix-associated laser desorption/ionization-time of flight. Tissue and blood samples are collected periodically for analysis including EGFR based on IHC and FISH, EGFR and k-Ras mutations, pAkt, pMAPK by IHC, and EMT markers based on IHC and breath condensate protein profile.