Table 2.

Molecular markers and response to the combination chemotherapy with gefitinib

Molecular markerNo. of patientsResponse rate* (%)P
EGFR expression
    Positive23480.12
    Negative40
KRAS mutation
    Mutant9330.69
    Wild-type1947
p21 expression
    Positive16250.05
    Negative1267
p53 mutation
    Positive21330.10
    Negative771
p21 and p53
    Both positive119.10.005
    Either one or both negative1669
p-AKT1 expression
    Positive7140.19
    Negative2250
p27 expression§
    Positive17530.25
    Negative1127
  • * Response rate is defined as the fraction of cases with partial response among the total number of cases with a particular molecular feature and known response status.

  • p21 positivity is defined as ≥10% of tumor cells staining.

  • p53 mutational status was determined by immunohistochemistry.

  • § p27 positivity is defined as >20% of tumor cells staining.