Table 1.
Baseline patient characteristics matched by propensity score.
| Variables | Total n = 140 |
NoABX n = 70 |
ABX n = 70 |
p-Value |
|---|---|---|---|---|
| Age | ||||
| Mean ± SD | 62.5 ± 11.1 | 63.2 ± 9.4 | 61.7 ± 12.6 | 0.693 |
| <65 years, n (%) | 78 (55.7) | 40 (57.1) | 38 (54.3) | 0.865 |
| ≥65 years, n (%) | 62 (44.3) | 30 (42.9) | 32 (45.7) | |
| Sex, n (%) | ||||
| Female | 40 (28.6) | 20 (28.6) | 20 (28.6) | 1.000 |
| Male | 100 (71.4) | 50 (71.4) | 50 (71.4) | |
| Stage, n (%) | ||||
| 2 | 3 (2.1) | 1 (1.4) | 2 (2.9) | 0.634 |
| 3 | 18 (12.9) | 11 (15.7) | 7 (10.0) | |
| 4 | 107 (76.4) | 51 (72.9) | 56 (80.0) | |
| Recurrence | 12 (8.6) | 7 (10.0) | 5 (7.1) | |
| ECOG performance status, n (%) | ||||
| 0 | 136 (97.1) | 69 (98.6) | 67 (95.7) | 0.620 |
| 1 | 4 (2.9) | 1 (1.4) | 3 (4.3) | |
| Tumor subtype, n (%) | ||||
| Adenocarcinoma | 98 (70.0) | 50 (71.4) | 48 (68.6) | 0.854 |
| Squamous cell carcinoma | 42 (30.0) | 20 (28.6) | 22 (31.4) | |
| Number of regimens before nivolumab | ||||
| <3, n (%) | 80 (57.1) | 41 (58.6) | 39 (55.7) | 0.864 |
| ≥3, n (%) | 60 (42.9) | 29 (41.4) | 31 (44.3) | |
| PD-L1 expression, n (%) | ||||
| High (≥50%) | 36 (25.7) | 19 (27.1) | 17 (24.3) | 0.918 |
| Moderate (≥10%, <50%) | 38 (27.1) | 19 (27.1) | 19 (27.1) | |
| Low (<10%) | 66 (47.1) | 32 (45.7) | 34 (48.6) | |