Table 1. Baseline patient characteristics.
| Variables | Total (n=403) |
|---|---|
| Median age [IQR], years | 65 [57–71] |
| Age, n (%) | |
| <70 years | 278 (69.0) |
| ≥70 years | 125 (31.0) |
| Sex, n (%) | |
| Male | 305 (75.7) |
| Female | 98 (24.3) |
| Smoking history, n (%) | |
| Yes | 77 (19.1) |
| No | 144 (35.7) |
| Unknown | 182 (45.2) |
| ECOG performance status, n (%) | |
| 0–1 | 346 (85.9) |
| ≥2 | 57 (14.1) |
| Histology, n (%) | |
| Non-squamous cell carcinoma | 261 (64.8) |
| Squamous cell carcinoma | 136 (33.8) |
| Unspecified | 6 (1.5) |
| Clinical stage, n (%) | |
| III | 72 (17.9) |
| IV | 331 (82.1) |
| Metastatic diseases | |
| Brain | 65 (16.1) |
| Liver | 48 (11.9) |
| Adrenal gland | 34 (8.4) |
| PD-L1 expression, n (%) | |
| <1% | 48 (11.9) |
| ≥1% | 52 (12.9) |
| 1–49% | 32 (7.9) |
| ≥50% | 20 (5.0) |
| Unknown | 303 (75.2) |
| EGFR/ALK mutation, n (%) | |
| Positive | 78 (19.4) |
| Negative | 101 (25.1) |
| Unknown | 224 (55.6) |
IQR, interquartile range; ECOG, Eastern Cooperative Oncology Group; PD-L1, programmed death ligand-1; EGFR, epidermal growth factor receptor; ALK, anaplastic lymphoma kinase.