Table 3 Univariate and multivariate Cox analysis of patients with stage III-IV SCLC

Age

  ≥ 70 vs < 70

1.44 (1.38,1.5)

 < 0.001

1.51 (1.45,1.57)

 < 0.001

Sex

 Male vs Female

1.18 (1.13,1.22)

 < 0.001

1.13 (1.09,1.17)

 < 0.001

Race

 Others vs Black

1.06 (0.95,1.18)

0.339

0.96 (0.86,1.07)

0.483

 White vs Black

1.09 (1.02,1.17)

0.008

1.03 (0.97,1.11)

0.323

T stage

 T1 vs T0

1.01 (0.84,1.21)

0.905

1.09 (0.9,1.3)

0.379

 T2 vs T0

1.21 (1.02,1.44)

0.032

1.25 (1.04,1.49)

0.014

 T3 vs T0

1.28 (1.08,1.53)

0.006

1.3 (1.09,1.55)

0.003

 T4 vs T0

1.26 (1.06,1.5)

0.01

1.3 (1.09,1.55)

0.003

N stage

 N1 vs N0

0.99 (0.9,1.1)

0.877

1.04 (0.94,1.15)

0.457

 N2 vs N0

1.04 (0.97,1.11)

0.268

1.2 (1.13,1.29)

 < 0.001

 N3 vs N0

1.12 (1.04,1.21)

0.002

1.24 (1.15,1.33)

 < 0.001

M stage

 M1 vs M0

2.07 (1.98,2.16)

 < 0.001

1.6 (1.51,1.68)

 < 0.001

Stage

 IV vs III

2.07 (1.98,2.16)

 < 0.001

-

-

Bilaterality

 Yes vs No

1.95 (1.56,2.43)

 < 0.001

1.37 (1.09,1.71)

0.006

Bone metastasis

 Yes vs No

1.6 (1.53,1.68)

 < 0.001

1.13 (1.08,1.19)

 < 0.001

Liver metastasis

 Yes vs No

1.88 (1.8,1.96)

 < 0.001

1.45 (1.38,1.52)

 < 0.001

Lung metastasis

 Yes vs No

1.48 (1.41,1.57)

 < 0.001

1.09 (1.03,1.16)

0.002

Brain metastasis

 Yes vs No

1.61 (1.53,1.69)

 < 0.001

1.39 (1.32,1.46)

 < 0.001