Table 1 Characteristics of patients in the training population and the validation population
|  | Training cohort (N = 63) | Validation cohort (N = 23) |
|---|---|---|
Age, mean (SD) | 61.9 (±10.7) | 58.7 (±8.7) |
Gender, male | 46 (73.0) | 10 (43.5) |
Smoking status | ||
 Never smoker | 1 (1.6) | 1 (4.3) |
 Ever smoker | 31 (49.2) | 21 (91.3) |
 Unknown | 31 (49.2) | 1 (4.3) |
ECOG performance score | ||
 0 or 1 |  | 17 (73.9) |
 2 |  | 5 (21.7) |
 Unknown | 63 (100) | 1 (4.3) |
Histology | ||
 ADC | 18 (28.6) | 21 (91.3) |
 LCC | 24 (38.1) | 2 (8.7) |
 SCC | 15 (23.8) |  |
 Other | 6 (9.5) |  |
Tumor stage | ||
 IA-IIB | 56 (88.9) |  |
 IIIA | 4 (6.3) |  |
 IIIB |  | 1 (4.3) |
 IV | 3 (4.8) | 22 (95.7) |
Treatment | ||
 Surgery | 63 (100) |  |
 CISPEM |  | 18 (78.3) |
 CARPEM |  | 5 (21.7) |
No. cycles chemotherapy, median (IQR) |  | 3 (3–4) |
Treatment effect | ||
 PR |  | 6 (26.1) |
 SD |  | 7 (30.4) |
 PD |  | 10 (43.5) |
 OS, median (IQR) | 28.0 (10.0–67.6) | 4.5 (3.2–7.3) |