Of 313 patients enrolled, 96 patients (31%) were assessable for EGFR mutations, and 42 patients (44%) had EGFR mutation–positive tumors. Deletional mutations in exon 19 and the L858R mutation in exon 21 of EGFR were detected in 27 patients (64%) and 15 patients (36%), respectively, and those mutations were mutually exclusive....In the EGFR mutation–positive subgroup, the gefitinib arm, compared with the GP arm, showed a higher ORR (84.6% [22 of 26 patients] v 37.5% [six of 16 patients], respectively; P = .002) and a trend toward longer PFS (HR, 0.544; 95% CI, 0.269 to 1.100; P = .086...