Table A2.
Baseline characteristics of the study cohort.
| Variables | All Patients | No OP/RT | OP or RT | p-Value |
|---|---|---|---|---|
| n | 186 | 107 | 79 | |
| Brain OP (operation for brain tumor) | 0 | 50 | ||
| Brain RT (radiotherapy for brain tumor) | 0 | 61 | ||
| Sex | ||||
| Female | 123 (66%) | 74 (69%) | 49 (62%) | 0.3096 |
| Male | 63 (34%) | 33 (31%) | 30 (38%) | |
| Age (year) | 65.5 ± 11.2 | 66.8 ± 11.0 | 63.8 ± 11.3 | 0.0688 |
| <65 | 92 (49%) | 49 (46%) | 43 (54%) | 0.2442 |
| ≥65 | 94 (51%) | 58 (54%) | 36 (46%) | |
| ECOG performance status | ||||
| 0–1 | 159 (85%) | 94 (88%) | 65 (82%) | 0.2863 |
| ≥2 | 27 (15%) | 13 (12%) | 14 (18%) | |
| Karnofsky performance status | ||||
| 100 | 12 (6%) | 8 (7%) | 4 (5%) | 0.2026 |
| 90 | 21 (11%) | 11 (10%) | 10 (13%) | |
| 80 | 125 (67%) | 77 (72%) | 48 (61%) | |
| 70 | 27 (15%) | 11 (10%) | 16 (20%) | |
| ≤60 | 1 (1%) | 0 (0%) | 1 (1%) | |
| EGFR mutation | ||||
| Exon 19 deletion | 85 (46%) | 48 (45%) | 37 (47%) | 0.7892 |
| Exon 21 L858R | 102 (55%) | 60 (56%) | 42 (53%) | 0.6934 |
| PD-L1 † | ||||
| <1% | 29 (29%) | 17 (27%) | 12 (32%) | 0.5299 |
| ≥1% | 72 (71%) | 47 (73%) | 25 (68%) | |
| Number of brain metastases | ||||
| 1 | 63 (34%) | 29 (27%) | 34 (43%) | 0.0600 |
| 2–4 | 55 (30%) | 33 (31%) | 22 (28%) | |
| ≥5 | 68 (37%) | 45 (42%) | 23 (29%) | |
| Number of ECM sites | ||||
| 0 | 25 (13%) | 8 (7%) | 17 (22%) | 0.0174 |
| 1–2 | 91 (49%) | 54 (50%) | 37 (47%) | |
| ≥3 | 70 (38%) | 45 (42%) | 25 (32%) | |
| Site of ECM | ||||
| Lung metastasis | 99 (53%) | 65 (61%) | 34 (43%) | 0.0167 |
| Pleural metastasis/effusion | 81 (44%) | 53 (50%) | 28 (35%) | 0.0554 |
| Bone metastasis | 116 (62%) | 72 (67%) | 44 (56%) | 0.1067 |
| Liver metastasis | 26 (14%) | 20 (19%) | 6 (8%) | 0.0310 |
| Pericardial metastasis/effusion | 51 (27%) | 32 (30%) | 19 (24%) | 0.3762 |
| Adrenal metastasis | 23 (12%) | 13 (12%) | 10 (13%) | 0.9170 |
| Other metastasis | 12 (6%) | 8 (7%) | 4 (5%) | 0.5078 |
| GPA (version 2010) score | ||||
| ≥2.5 | 26 (14%) | 9 (8%) | 17 (22%) | 0.0021 |
| 1.5–2.0 | 66 (35%) | 33 (31%) | 33 (42%) | |
| ≤1.0 | 94 (51%) | 65 (61%) | 29 (37%) | |
| GPA (version 2017) score | ||||
| ≥2.5 | 36 (19%) | 12 (11%) | 24 (30%) | 0.0048 |
| 1.5–2.0 | 120 (65%) | 76 (71%) | 44 (56%) | |
| ≤1.0 | 30 (16%) | 19 (18%) | 11 (14%) | |
| GPA (version 2022) score | ||||
| ≥3.0 | 17 (9%) | 6 (6%) | 11 (14%) | 0.1327 |
| 1.5–2.5 | 149 (80%) | 88 (82%) | 61 (77%) | |
| ≤1.0 | 20 (11%) | 13 (12%) | 7 (9%) | |
| EGFR TKI | ||||
| Gefitinib | 27 (15%) | 11 (10%) | 16 (20%) | 0.0022 |
| Erlotinib | 104 (56%) | 68 (64%) | 36 (46%) | |
| Afatinib | 48 (26%) | 21 (20%) | 27 (34%) | |
| Osimertinib | 7 (4%) | 7 (7%) | 0 (0%) | |
| Anti-VEGF treatment | ||||
| No | 175 (94%) | 101 (94%) | 74 (94%) | 0.8366 |
| Yes | 11 (6%) | 6 (6%) | 5 (6%) |
Abbreviations: ECM, extracranial metastasis; ECOG, Eastern Cooperative Oncology Group; EGFR, epidermal growth factor receptor; GPA, graded prognostic assessment; OP, surgery for brain tumor; PD-L1, programmed death ligand 1; RT, radiotherapy for brain tumor; TKI, tyrosine kinase inhibitor; VEGF, vascular endothelial growth factor. Data are presented as n (%) or mean ± standard deviation. p-values are presented for results of the chi-squared test or analysis of variance. † PD-L1 was examined in 101 patients.