Table 1. Patient baseline characteristics.
| Characteristics | Total (n=159) | ICI-mono (n=80) | ICI-chemo (n=79) | P |
|---|---|---|---|---|
| Median age [range], year | 71 [31–89] | 74 [46–89] | 68 [31–81] | <0.001 |
| Sex, n (%) | 0.402 | |||
| Men | 128 (80.5) | 62 (77.5) | 66 (83.5) | |
| Women | 31 (19.5) | 18 (22.5) | 13 (16.5) | |
| Age group, n (%) | <0.001 | |||
| <75 years | 109 (68.6) | 42 (52.5) | 67 (84.8) | |
| ≥75 years | 50 (31.4) | 38 (47.5) | 12 (15.2) | |
| Smoking status, n (%) | 0.740 | |||
| Brinkman index ≥400 | 122 (76.7) | 60 (75.0) | 62 (78.5) | |
| ECOG-PS, n (%) | <0.001 | |||
| 0 or 1 | 128 (80.5) | 51 (63.8) | 77 (97.5) | |
| ≥2 | 31 (19.5) | 29 (36.2) | 2 (2.5) | |
| Histological subtypes, n (%) | 0.200 | |||
| Adenocarcinoma | 104 (65.4) | 49 (61.3) | 55 (69.6) | |
| Squamous cell carcinoma | 38 (23.9) | 19 (23.8) | 19 (24.1) | |
| NSCLC, NOS | 17 (10.7) | 12 (15.0) | 5 (6.3) | |
| Staging, n (%) | 0.006 | |||
| Recurrence | 32 (20.1) | 24 (30.0) | 8 (10.1) | |
| 3 | 10 (6.3) | 5 (6.3) | 5 (6.3) | |
| 4A | 44 (27.7) | 15 (18.8) | 29 (36.7) | |
| 4B | 73 (45.9) | 36 (45.0) | 37 (46.8) | |
| Presence of brain metastasis, n (%) | 29 (18.2) | 16 (20.0) | 13 (16.5) | 0.709 |
| Presence of bone metastasis, n (%) | 60 (37.7) | 30 (37.5) | 30 (37.9) | 1.000 |
| Presence of liver metastasis, n (%) | 21 (13.2) | 13 (16.3) | 8 (10.1) | 0.365 |
| PD-L1 expression, n (%) | <0.001 | |||
| <1% | 24 (15.1) | 0 (0.0) | 24 (30.4) | |
| 1–49% | 33 (20.8) | 12 (15.0) | 21 (26.6) | |
| ≥50% | 86 (54.1) | 68 (85.0) | 18 (22.8) | |
| Unknown | 16 (10.1) | 0 (0.0) | 16 (20.3) | |
| Treatment regimen, n (%) | <0.001 | |||
| Pembrolizumab (monotherapy) | 80 (50.3) | 80 (100.0) | 0 (0.0) | |
| Pembrolizumab + platinum + pemetrexed | 49 (30.8) | 0 (0.0) | 49 (62.0) | |
| Pembrolizumab + carboplatin + nab-paclitaxel | 22 (13.8) | 0 (0.0) | 22 (27.8) | |
| Atezolizumab + carboplatin + paclitaxel + bevacizumab | 5 (3.1) | 0 (0.0) | 5 (6.3) | |
| Atezolizumab + carboplatin + nab-paclitaxel | 3 (1.9) | 0 (0.0) | 3 (3.8) | |
| LIPI score, n (%) | 0.136 | |||
| Good | 66 (41.2) | 27 (33.8) | 39 (49.4) | |
| Intermediate | 77 (48.4) | 44 (55.0) | 33 (41.7) | |
| Poor | 16 (10.1) | 9 (11.3) | 7 (8.9) | |
| Number of organs involved | 0.111 | |||
| Median (IQR) | 3.0 (2.0–4.0) | 3.0 (2.0–4.0) | 2.0 (2.0–4.0) | |
| Max BTS | 0.608 | |||
| Median (IQR) | 54.2 (37.2–72.5) | 54.5 (40.2–74.1) | 54.0 (36.6–69.0) | |
| Total BTS | 0.476 | |||
| Median (IQR) | 104.3 (67.7–151.1) | 108.7 (76.9–163.9) | 100.6 (62.9–146.3) | |
| Number of target lesions | 0.150 | |||
| Median (IQR) | 3.0 (2.0–4.0) | 3.0 (2.0–5.0) | 3.0 (2.0–4.0) |
ICI, immune checkpoint inhibitor; ICI-mono, ICI monotherapy; ICI-chemo, ICI in combination with chemotherapy; ECOG-PS, Eastern Cooperative Oncology Group performance status; NSCLC, non-small cell lung cancer; NOS, not otherwise specified; PD-L1, programmed death ligand-1; LIPI, lung immune prognostic index; IQR, interquartile range; BTS, baseline tumor size; max BTS, maximum BTS.