TABLE 2

Risk of occult N2 disease according to each definition of a centrally located tumour in patients with radiological N0 nonsmall cell lung cancer

Definition of central locationPatients n (%)Crude modelModel 1#Model 2
Unadjusted OR (95% CI)p-valueAdjusted OR (95% CI)p-valueAdjusted OR (95% CI)p-value
Contact with the hilar structure122 (9.1)1.86 (1.02−3.40)0.0421.16 (0.59−2.29)0.6711.26 (0.63−2.54)0.510
Concentric lines arising from the hilum
 Inner one-third216 (16.2)1.91 (1.17–3.11)0.0101.29 (0.75–2.23)0.3581.33 (0.77–2.31)0.311
 Inner two-thirds642 (48.0)1.54 (1.01–2.37)0.0461.09 (0.68–1.73)0.7301.06 (0.66–1.70)0.808
Concentric lines arising from the midline
 Inner one-third161 (12.0)2.63 (1.59−4.36)<0.0012.05 (1.14−3.71)0.0172.13 (1.17−3.87)0.013
 Inner two-thirds696 (52.1)2.03 (1.29−3.18)0.0021.50 (0.92−2.46)0.1041.48 (0.90−2.42)0.121
Sagittal lines arising from the midline
 Inner one-third358 (26.8)1.81 (1.17−2.80)0.0081.57 (0.90−2.73)0.1131.59 (0.91−2.79)0.101
 Inner two-thirds1073 (80.3)1.30 (0.74−2.30)0.3650.89 (0.49−1.63)0.7120.90 (0.49−1.64)0.721

#: adjusted for tumour size (continuous) and tumour attenuation on computed tomography (tumour histology and number of dissected nodes and stations during mediastinal lymph node dissection were not included since this information was not available pre-operatively); : further adjusted for age (continuous), sex, smoking history (never-smoker or ever-smoker) and lobar location (right or left) of tumour.