Table 1.

Demographic characteristics of the study population

CharacteristicControls (n = 24)Cases (n = 59)Clinical stage
IA (n = 16)IB (n = 8)II (n = 7)III (n = 10)IV (n = 18)
Gender, n (%) male9 (37.5)30 (50.8)11 (78.6)4 (50.0)2 (22.2)5 (50.0)8 (44.4)
    P*0.27
Age (mean ± SEM)55.5 ± 2.8666.8 ± 1.3667.4 ± 2.5570.63 ± 3.6761.0 ± 3.0167.7 ± 2.9466.9 ± 2.88
    P*0
Ever smokers (%)45.8389.8381.257510090100
    P*<0.001
Pack-years (mean ± SEM)53.1 ± 12.4845.0 ± 3.3744.6 ± 8.4148.0 ± 6.9945.4 ± 10.145.1 ± 5.9743.8 ± 6.43
    P*0.7
Histology, n (%)
    Squamous12 (20.3)6 (37.5)2 (25.0)2 (28.6)1 (10.0)1 (5.6)
    Adenocarcinoma32 (54.2)9 (64.3)5 (62.5)5 (71.4)4 (40.0)9 (50.0)
    NSC15 (25.4)1 (7.1)1 (12.5)0 (0.0)5 (50.0)8 (44.4)
Patients who died, n (%)22 (37.3)1 (4.5)0 (0.0)0 (0.0)6 (27.3)15 (68.2)

NOTE: χ2 test for association (categorical variables); all P values are two-sided and compare controls to all cases.

Abbreviation: NSC, non–small cell carcinoma.

  • *P value derived from Mann-Whitney test (continuous variables).