Table 1.

EGFR mutation status, EGFR gene copy number status, and KRAS mutation status by patients' characteristics

CharacteristicEGFR mutation status (tested, 71 of 73)
EGFR gene copy number status(tested, 59 of 73)
KRAS mutation status (tested, 70 of 73)
Wild type (n = 64), n (%)Mutated (n = 7), n (%)P*Not increased (n = 27), n (%)Increased (n = 32), n (%)P*Wild type (n = 54), n (%)Mutated (n = 16), n (%)P*
Age, median, y60510.264580.1957.5650.05
Gender
    Female36 (87.8)5 (12.2)0.6918 (54.5)15 (45.5)0.1930 (73.2)11 (26.8)0.4
    Male28 (93.3)2 (6.7)9 (34.6)17 (65.4)24 (82.8)5 (17.2)
Race
    Asian4 (57.1)3 (42.9)0.034 (80.0)1 (20)0.347 (100)0 (0)0.41
    Caucasian52 (92.9)4 (7.1)21 (42.9)28 (57.1)41 (74.5)14 (25.5)
    Other8 (100)0 (0)2 (40)3 (60)6 (75)2 (25)
Smoking history
    Current smoker23 (95.8)1 (4.2)0.1510 (50)10 (50)0.2818 (78.3)5 (21.7)0.1
    Former smoker28 (93.3)2 (6.7)9 (34.6)17 (65.4)20 (66.7)10 (33.3)
    Never smoker13 (76.5)4 (23.5)8 (61.5)5 (38.5)16 (94.1)1 (5.9)
Histology
    Adenocarcinoma40 (85.1)7 (14.9)0.2217 (43.6)22 (56.4)0.9334 (72.3)13 (27.7)0.13
    NSCLC13 (100)05 (55.6)4 (44.4)9 (75)3 (25)
    Squamous cell carcinoma11 (100)05 (45.5)6 (54.5)11 (100)0
PS (ECOG)
    0-132 (82.1)7 (17.9)0.0114 (43.8)18 (56.3)0.831 (81.6)7 (18.4)0.4
    2-332 (100)013 (48.1)14 (51.9)23 (71.9)9 (28.1)
Stage
    IIIB5 (100)01.03 (75)1 (25)0.325 (100)00.58
    IV59 (89.4)7 (10.6)24 (43.6)31 (56.4)49 (75.4)16 (24.6)
Previous chemotherapy regimens
    010 (90.9)1 (9.1)1.06 (54.5)5 (45.5)0.347 (63.6)4 (36.4)0.35
    123 (92)2 (8)11 (55)9 (45)21 (84)4 (16)
    ≥231 (88.6)4 (11.4)10 (35.7)18 (64.3)26 (76.5)8 (23.5)
Pleural effusion
    No37 (88.1)5 (11.9)0.6915 (40.5)22 (59.5)0.4230 (73.2)11 (26.8)0.4
    Yes27 (93.1)2 (6.9)12 (54.5)10 (45.5)24 (82.8)5 (17.2)
Brain metastasis
    No42 (91.3)4 (8.7)0.6921 (58.3)15 (41.7)0.0234 (74)12 (26)0.55
    Yes22 (88)3 (12)6 (26.1)17 (73.9)20 (83.3)4 (16.7)
  • Abbreviations: PS, performance status; ECOG, Eastern Cooperative Oncology Group.

  • * χ2 test or Fisher's exact test.

  • Data retrieved at start of gefitinib or erlotinib treatment.