There is no clear correlation between EGFR expression and response to Erlotinib, Gefitinib or Cetuximab efficacy in NSCLC or colorectal cancer (Saltz et al, 2001; Fukuoka et al, 2003; Johnson and Arteaga, 2003; Perez-Soler, 2004; Saltz et al, 2004; Noberasco et al, 2005). This evidence concerns the gene EGFR and non-small cell lung carcinoma.