Table 1.
Clinical characteristics of the patient sample at the baseline
| Overall | Chemotherapy plus ICI | Chemotherapy alone | P | |
|---|---|---|---|---|
| n = 245 | n = 105 | n = 140 | ||
| Age (years) | ||||
| median [Range] | 64 [36, 84] | 65 [42, 84] | 62 [36, 75] | 0.002 |
| Sex (%) | ||||
| Female | 21 (9) | 8 (8) | 13 (9) | 0.818 |
| Male | 224 (91) | 97 (92) | 127 (91) | |
| Smoke (%) | ||||
| Never smoker | 16 (7) | 8 (8) | 8 (6) | 0.737 |
| Current/former smoker | 229 (93) | 97 (92) | 132 (94) | |
| ECOG score (%) | ||||
| 0 | 34 (14) | 13 (12) | 21 (15) | 0.689 |
| 1 | 211 (86) | 92 (88) | 119 (85) | |
| CRP (mg/L) | ||||
| median [IQR] | 14 [5, 38] | 14 [3, 41] | 14 [5, 37] | 0.546 |
| Normal a | 84 (34) | 42 (40) | 42 (30) | 0.135 |
| Elevated | 161 (66) | 63 (60) | 98 (70) | |
| LDH (U/L) | ||||
| median [IQR] | 196 [168, 259] | 196 [172, 253] | 194 [163, 273] | 0.599 |
| Normal a | 174 (71) | 99 (71) | 75 (71) | 0.917 |
| Elevated | 71 (29) | 41 (29) | 30 (29) | |
| NLR | ||||
| median [IQR] | 4 [3, 6] | 4 [2, 6] | 4 [3, 6] | 0.285 |
| < 3 | 162 (66) | 72 (69) | 90 (64) | 0.572 |
| ≥3 | 83 (34) | 33 (31) | 50 (36) | |
| PD-L1 expression on tumor cells | ||||
| < 1% | 24 (10) | 17 (16) | 7 (5) | 0.239 b |
| 1–49% | 32 (13) | 20 (19) | 12 (9) | |
| ≥50% | 15 (6) | 13 (12) | 2 (1) | |
| Unknown | 174 (71) | 55 (52) | 119 (85) | |
| Brain metastases (%) | ||||
| Absence | 223 (91) | 96 (91) | 127 (91) | 1 |
| Presence | 22 (9) | 9 (9) | 13 (9) | |
| Liver metastases (%) | ||||
| Absence | 199 (81) | 85 (81) | 114 (81) | 1 |
| Presence | 46 (19) | 20 (19) | 26 (19) | |
| Bone metastases (%) | ||||
| Absence | 168 (69) | 70 (67) | 98 (70) | 0.677 |
| Presence | 77 (31) | 35 (33) | 42 (30) | |
| Type of ICI | ||||
| Pembrolizumab | 38 (16) | 38 (36) | ||
| Nivolumab | 25 (10) | 25 (24) | ||
| Atezolizumab | 12 (5) | 12 (11) | ||
| Sintilimab | 9 (4) | 9 (9) | ||
| Camrelizumab | 5 (2) | 5 (5) | ||
| others | 12 (5) | 12 (11) |
Abbreviations: CRP C-reactive protein, NLR neutrophil to lymphocyte ratio, LDH lactate dehydrogenase, ECOG Eastern Cooperative Oncology Group, PD-L1 programmed cell death 1 ligand 1, ICI immune checkpoint inhibitor, SD standard deviation; n, number of patients
a Baseline CRP level and LDH level were deemed elevated if they exceeded the individual center’s reference value; otherwise, they were considered normal. b Statistics do not include the unknown