EGFR and lung adenocarcinoma: After pivotal trials proved strong activity of gefitinib in patients with EGFR mutation-positive (del19, L858R) lung adenocarcinoma [6,7], subsequent phase II trials demonstrated the efficacy of gefitinib in the upfront treatment setting with an ORR of 55% to 75% and a median PFS of 9.2 to 9.7 months [80,81].