Skip to main content

Table 1 Baseline characteristics of training cohort and external validation cohort

From: Dynamic nomograms combining N classification with ratio-based nodal classifications to predict long-term survival for patients with lung adenocarcinoma after surgery: a SEER population-based study

Characteristic Total
(n = 25,005)
Training cohort
(n = 13,551)
External validation cohort
(n = 11,454)
P value
N % N % N %
Age at diagnosis (year)        < 0.001
  < 50 1288 5.2 806 5.9 482 4.2  
 50–59 4898 19.6 2967 21.9 1931 16.9  
 60–69 8830 35.3 4829 35.6 4001 34.9  
 70–79 7683 30.7 3894 28.7 3789 33.1  
  ≥ 80 2306 9.2 1055 7.8 1251 10.9  
Sex        0.021
 Male 10,680 42.7 5878 43.4 4802 41.9  
 Female 14,325 57.3 7673 56.6 6652 58.1  
Race        < 0.001
 White 20,416 81.6 11,639 85.9 8777 76.6  
 Black 2287 9.1 1638 12.1 649 5.7  
 Other 2302 9.2 274 2.0 2028 17.7  
Marital status at diagnosis        < 0.001
 Single 2942 11.8 1479 10.9 1463 12.8  
 Married 14,917 59.7 8095 59.7 6822 59.6  
 Other 7146 28.6 3977 29.3 3169 27.7  
Laterality        0.026
 Right 15,015 60.0 8223 60.7 6792 59.3  
 Left 9990 40.0 5328 39.3 4662 40.7  
Site        0.006
 Main bronchus 40 0.2 21 0.2 19 0.2  
 Upper lobe 15,359 61.4 8454 62.4 6905 60.3  
 Middle lobe 1317 5.3 674 5.0 643 5.6  
 Lower lobe 7983 31.9 4231 31.2 3752 32.8  
 Over lapping lesion of lung 306 1.2 171 1.3 135 1.2  
Differentiation        < 0.001
 I (Well differentiated) 4568 18.3 2298 17.0 2270 19.8  
 II (Medium differentiated) 12,401 49.6 6655 49.1 5746 50.2  
 III (Poorly differentiated) 7851 31.4 4506 33.3 3345 29.2  
 IV (Undifferentiated) 185 0.7 92 0.7 93 0.8  
T classification        0.028
 T1 11,856 47.4 6529 48.2 5327 46.5  
 T2 8832 35.3 4701 34.7 4131 36.1  
 T3 2976 11.9 1580 11.7 1396 12.2  
 T4 1341 5.4 741 5.5 600 5.2  
N classification        0.502
 N0 18,541 74.1 10,080 74.4 8461 73.9  
 N1 3366 13.5 1774 13.1 1592 13.9  
 N2 3098 12.4 1697 12.5 1401 12.2  
Type of surgery        < 0.001
 Sublobectomy 2831 11.3 1707 12.6 1124 9.8  
 Lobectomy 21,499 86.0 11,441 84.4 10,058 87.8  
 Pneumonectomy 675 2.7 403 3.0 272 2.4  
Radiotherapy        < 0.001
 No 22,786 91.1 12,262 90.5 10,524 91.9  
 Yes 2219 8.9 1289 9.5 930 8.1  
Chemotherapy        < 0.001
 No 18,282 73.1 9737 71.9 8545 74.6  
 Yes 6723 26.9 3814 28.1 2909 25.4  
NDLN        0.277
 NDLN1 (1–10) 15,958 63.8 8717 64.3 7241 63.2  
 NDLN2 (11–19) 6399 25.6 3345 24.7 3054 26.7  
 NDLN3 (≥20) 2648 10.6 1489 11.0 1159 10.1  
NPLN        0.301
 NPLN0 (0) 18,726 74.9 10,186 75.2 8540 74.6  
 NPLN1 (1–6) 5656 22.6 3022 22.3 2634 23.0  
 NPLN2 (≥7) 623 2.5 343 2.5 280 2.4  
LODDS        0.371
 LODDS1 (<−0.94) 15,712 62.8 8427 62.2 7285 63.6  
 LODDS2 (≥ − 0.94, <−0.41) 6211 24.8 3451 25.5 2760 24.1  
 LODDS3 (≥ − 0.41) 3082 12.3 1673 12.3 1409 12.3  
LNR        0.045
 LNR0 (0) 18,726 74.9 10,186 75.2 8540 74.6  
 LNR1 (> 0, < 0.55) 5120 20.5 2716 20.0 2404 21.0  
 LNR2 (≥0.55, ≤1) 1159 4.6 649 4.8 510 4.5  
  1. NDLN number of dissected lymph nodes; NPLN number of positive lymph nodes; LODDS log odds of positive lymph nodes; LNR lymph node ratio