Patient characteristics
| Pembrolizumab cohort 950 N° (%) | Chemotherapy cohort 595 N° (%) | ||
| Age (years) | χ2 test | ||
| Median | 70.1 | 67 | p<0.0001 |
| Range | 28–92 | 31–91 | |
| Elderly (≥70) | 483 (50.8) | 239 (40.2) | |
| Gender | p=0.4314 | ||
| Male | 625 (65.8) | 403 (67.7) | |
| Female | 325 (34.2) | 192 (32.3) | |
| ECOG-PS | p=0.0319 | ||
| 0–1 | 785 (82.6) | 516 (86.7) | |
| ≥2 | 165 (17.4) | 79 (13.3) | |
| Histology | p=0.4097 | ||
| Squamous | 210 (22.1) | 121 (20.3) | |
| Non-squamous | 740 (77.9) | 474 (79.7) | |
| Smoking status | p=0.5094 | ||
| Never smokers | 103 (10.8) | 71 (11.9) | |
| Current/former smokers | 847 (89.2) | 524 (88.1) | |
| CNS metastases | p=0.9766 | ||
| Yes | 173 (18.2) | 108 (18.2) | |
| No | 777 (81.8) | 487 (81.8) | |
| Bone metastases | p=0.0753 | ||
| Yes | 319 (33.6) | 174 (29.2) | |
| No | 631 (66.4) | 421 (70.8) | |
| Liver metastases | p=0.5615 | ||
| Yes | 146 (15.4) | 85 (14.3) | |
| No | 804 (84.6) | 510 (85.7) | |
| Corticosteroids | p=0.0102 | ||
| No | 722 (76.1) | 417 (70.1) | |
| Yes | 228 (24.0) | 178 (29.9) | |
| Antibiotics | p=0.6475 | ||
| No | 819 (86.2) | 508 (85.4) | |
| Yes | 131 (13.8) | 87 (14.6) | |
| PPIs | p=0.1208 | ||
| No | 476 (50.1) | 274 (46.1) | |
| Yes | 474 (49.9) | 321 (53.69) | |
| Statins | p=0.0701 | ||
| No | 698 (73.5) | 462 (77.6) | |
| Yes | 252 (26.5) | 133 (22.4) | |
| Aspirin | p=0.0746 | ||
| No | 696 (73.3) | 460 (77.3) | |
| Yes | 254 (26.7) | 135 (22.7) | |
| β-blockers | p=0.0003 | ||
| No | 692 (72.8) | 481 (80.8) | |
| Yes | 258 (27.2) | 114 (19.2) | |
| Metformin | p=0.0556 | ||
| No | 825 (86.8) | 536 (90.1) | |
| Yes | 125 (13.2) | 59 (9.9) |
CNS, central nervous system; ECOG-PS, Eastern Cooperative Oncology Group-Performance Status; PPIs, proton pump inhibitors.