Discovery cohort | Validation cohort | P | |
---|---|---|---|
Age at surgery (year, median [IQR]) | 61.0 (54.5–67.0) | 56.0 (49.0–63.0) | < 0.001a |
< 65 | 95 (65.5%) | 143 (79.4%) | 0.005b |
≥ 65 | 50 (34.5%) | 37 (20.6%) | |
Sex | 0.997b | ||
Male | 83 (57.2%) | 103 (57.2%) | |
Female | 62 (42.8%) | 77 (42.8%) | |
Smoking history | 0.027b | ||
Never | 101 (69.7%) | 104 (57.8%) | |
Former/current | 44 (30.3%) | 76 (42.2%) | |
pT stage | < 0.001b | ||
T1 | 44 (30.3%) | 132 (73.3%) | |
T2 | 78 (53.8%) | 33 (18.3%) | |
T3 | 16 (11.0%) | 7 (3.9%) | |
T4 | 7 (4.8%) | 8 (4.4%) | |
pN stage | 0.382b | ||
N0 | 109 (75.2%) | 132 (73.3%) | |
N1 | 12 (8.3%) | 23 (12.8%) | |
N2 | 24 (16.6%) | 25 (13.9%) | |
TNM stage | 0.815b | ||
I | 92 (63.4%) | 114 (63.3%) | |
II | 21 (14.5%) | 30 (16.7%) | |
III | 32 (22.1%) | 36 (20.0%) | |
Tumour location | 0.051b | ||
Upper/middle lobe | 96 (66.2%) | 100 (55.6%) | |
Lower lobe | 49 (33.8%) | 80 (44.4%) | |
Histologic type | 0.001c | ||
Adenocarcinoma | 111 (76.6%) | 143 (79.4%) | |
Squamous cell carcinoma | 23 (15.9%) | 37 (20.6%) | |
Other | 11 (7.6%) | 0 (0.0%) | |
Differentiation grade | 0.005b | ||
Well-moderately differentiated (G1/G2) | 107 (73.8%) | 106 (58.9%) | |
Poorly-undifferentiated (G3/G4) | 38 (26.2%) | 74 (41.1%) | |
Type of surgery | 0.046b | ||
Lobectomy/pneumonectomy | 134 (92.4%) | 175 (97.2%) | |
Limited resection | 11 (7.6%) | 5 (2.8%) | |
Adjuvant chemotherapy | < 0.001b | ||
No | 94 (64.8%) | 74 (41.1%) | |
Yes | 51 (35.2%) | 106 (58.9%) | |
Follow-up duration (month, median [95% CI]) | 102.7 (89.7–115.6) | 60.0 (57.1–62.8) | < 0.001d |
No. of events | 72 (49.7%) | 78 (43.3%) | 0.256b |