Table 2.

Molecular characteristics and gefitinib responsiveness

Total no.No. responders (%)P
EGFR mutation
    Mutation (−)548 (14.8)0.004*
    Mutation (+)158 (53.3)
EGFR gene copy number
    Low copy number354 (11.4)0.039
    High copy number3110 (32.3)
K-ras mutation
    Mutation (−)6016 (26.7)0.10*
    Mutation (+)90 (0)
HER2 mutation
    Mutation (−)5311 (20.8)0.58*
    Mutation (+)40 (0)
PTEN expression
    Reduced224 (18.2)0.56
    Intact4712 (25.5)
Akt phosphorylation
    Negative/weak5013 (26)0.53*
    Strong193 (15.8)
Erk phosphorylation
    Negative259 (36)0.057
    Positive447 (15.9)
  • * Fisher's exact test.

  • Pearson's χ2 test.