EGFR and colorectal cancer: Importantly, the clinical benefit observed with anti-EGFR TKIs across different disease entities has been variable (eg, EGFR TKIs are largely inactive in colorectal cancer); however, two of these drugs, gefitinib and erlotinib, have demonstrated clinical activity in nonsmall cell lung cancer (NSCLC) and responses have been observed in patients with advanced pancreatic cancer and in head-and-neck cancer (Baselga, 2006).