Table 1 Summary of characteristics in training and testing cohorts

From: A PET/CT nomogram incorporating SUVmax and CT radiomics for preoperative nodal staging in non-small cell lung cancer

Characteristics Training cohort Testing cohort p## value
LN (+) (N = 89) LN (−) (N = 96) p value LN (+) (N = 38) LN (−) (N = 40) p value
Sex, no. (%)    0.075    0.581 0.910
From male patients 44 (16.73) 35 (13.31)   21 (7.98) 20 (7.60)   
From female patients 45 (17.11) 61(23.19)   17 (6.46) 20 (7.60)   
Age/mean ± SD, years 58.35 ± 6.76 59.23 ± 7.55 0.406 58.37 ± 8.22 58.55 ± 10.09 0.931 0.745
Pathology source (no. (%))    0.294    0.502 0.228
SCC 25 (9.88) 20 (6.84)   9 (3.42) 12 (4.74)   
Adenocarcinoma 62 (24.51) 76 (28.90)   28 (11.07) 28 (10.65)   
NEC 1 (0.38) 0 (0.00)   1 (0.38) 0 (0.00)   
Sarcoma 1 (0.38) 0 (0.00)   0 (0.00) 0 (0.00)   
LN station (no. (%))    0.048    0.002 0.208
  #1, #2 10 (3.80%) 4 (1.52%)   7 (2.66%) 0 (0.00%)   
  #3–9 32 (12.17%) 49 (18.63%)   15 (5.70%) 10 (3.80%)   
  #10–14 47 (17.87%) 43 (16.35%)   16 (6.08%) 30 (11.41%)   
Lung lobe (no. (%))    0.046    0.420 0.847
Right upper lobe 25 (9.51%) 28 (10.65%)   10 (3.80%) 9 (3.42%)   
Right middle lobe 4 (1.52%) 16 (6.08%)   4 (1.52%) 5 (1.90%)   
Right lower lobe 17 (6.46%) 21 (7.98%)   8 (3.04%) 9 (3.42%)   
Left upper lobe 17 (6.46%) 14 (5.32%)   11 (4.18%) 6 (2.28%)   
Left lower lobe 26 (9.89%) 17 (6.46%)   5 (1.90%) 11 (4.18%)   
SUVmax/median (25%, 75%) 3.95 (2.92, 6.54) 2.29 (1.51, 3.50) < 0.001 4.15 (3.28, 8.68) 2.22 (3.16, 3.42) < 0.001 0.759
SAD/median (25%,75%) (cm) 1.00 (0.80, 1.38) 0.90 (0.70, 1.00) < 0.001 1.05 (0.90, 1.35) 0.80 (0.60, 1.08) < 0.001 0.754
Rad-Score 0.582 (− 0.221, 1.892) − 0.808 (− 1.779, − 2.000) < 0.001 0.702 (0.255, 1.991) − 0.677(− 1.230, 0.228) < 0.001 0.242
Int-Score 1.387 (− 0.014, 3.109) − 1.438 (− 2.402, − 0.293) < 0.001 1.405 (− 0.030, 3.060) − 1.297 (− 2.422, − 0.119) < 0.001 0.449
  1. The values in italics indicate the cut-off values used in the diagnosis process
  2. p < 0.001 indicates statistical significance
  3. SCC, squamous cell carcinoma; NEC, neuroendocrine carcinoma
  4. Lymph nodes and tumors were located on the same side of the trachea or esophagus
  5. Lung lobe represents the tumor location
  6. p## value indicates the significance of differences between the characteristics in training and testing cohorts
  7. p value indicates the significance of differences between the LN (+) group and LN (−) group