Patients’ characteristics
| Pembrolizumab cohort 962 n (%) | Chemotherapy cohort 426 n (%) | χ2 test | Pembrolizumab cohort (4 weeks landmark) 799 n (%) | Chemotherapy cohort (4 weeks landmark) 414 n (%) | χ2 test | |
| Age (years) | ||||||
| Median | 70.1 | 66.0 | 70.2 | 66.0 | ||
| Range | 28–92 | 24–85 | p<0.0001 | 28–92 | 24–84 | p=0.0002 |
| Elderly (≥70) | 491 (51.0) | 167 (39.2) | 410 (51.3) | 165 (39.9) | ||
| Smoking status | ||||||
| Former/current | 864 (89.8) | 378 (88.7) | p=0.5452 | 719 (90.0) | 369 (89.1) | p=0.6417 |
| Never | 98 (10.2) | 48 (11.3) | 80 (10.0) | 45 (10.9) | ||
| Sex | ||||||
| Male | 635 (66.0) | 295 (69.2) | p=0.2365 | 535 (67.0) | 288 (69.6) | p=0.3569 |
| Female | 327 (34.0) | 131 (30.8) | 264 (33.0) | 126 (30.4) | ||
| ECOG PS | ||||||
| 0–1 | 793 (82.4) | 396 (93.0) | p<0.0001 | 685 (85.7) | 385 (93.0) | p=0.0002 |
| ≥2 | 169 (17.6) | 30 (7.0) | 114 (14.3) | 29 (7.0) | ||
| Histology | ||||||
| Squamous | 232 (24.1) | 95 (22.3) | p=0.4623 | 188 (23.5) | 95 (22.9) | p=0.8201 |
| Non-squamous | 730 (75.9) | 331 (77.7) | 611 (76.5) | 319 (77.1) | ||
| CNS metastases | ||||||
| Yes | 171 (17.8) | 67 (15.7) | p=0.3507 | 138 (17.3) | 66 (15.9) | p=0.5574 |
| No | 791 (82.2) | 359 (84.3) | 661 (82.7) | 348 (84.1) | ||
| Bone metastases | ||||||
| Yes | 310 (32.2) | 115 (27.0) | p=0.0513 | 240 (30.0) | 112 (27.1) | p=0.2777 |
| No | 652 (67.8) | 311 (73.0) | 559 (70.0) | 302 (72.9) | ||
| Liver metastases | ||||||
| Yes | 150 (15.7) | 57 (13.4) | p=0.2730 | 119 (14.9) | 56 (13.5) | p=0.5207 |
| No | 808 (84.3) | 369 (86.6) | 680 (85.1) | 358 (86.5) | ||
| BMI (kg/m2) | ||||||
| Median (range) | 24.2 (14.0–44.9) | 24.9 (15.7–41.8) | 24.2 (14.0–44.9) | 24.9 (15.7–41.8) | ||
| Underweight (≤18.5) | 40 (4.2) | 16 (3.8) | p=0.0505 | 40 (4.2) | 10 (2.4) | p=0.0210 |
| Normal weight (18.5–25) | 526 (54.9) | 202 (47.4) | p=0.0287* | 526 (54.9) | 200 (48.3) | p=0.0089* |
| Overweight (25–30) | 275 (28.7) | 150 (35.2) | 275 (28.7) | 147 (35.5) | ||
| Obese (≥30) | 117 (12.2) | 58 (13.6) | 117 (12.2) | 57 (13.8) | ||
| ΔBMI (sample) | – | – | (799) (83.1) | (414) (97.2) | ||
| Median | – | – | 0% | 0% | ||
| Range | (−34% to +34%) | (−22% to +27%) |
*χ2 test for trend.
BMI, body mass index; CNS, central nervous system; ECOG-PS, Easter Cooperative Oncology Group—Performance Status.