Table 1.
Demographics and clinical characteristics of the study population.
| Characteristics | Overall cohort | Training Cohort | Validation Cohort |
|---|---|---|---|
| N = 356 | (n = 230) | (n = 126) | |
| Gender, n (%) | |||
| Male | 188 (52.8%) | 120 (52.2%) | 68 (54.0%) |
| Female | 168 (47.2%) | 110 (47.8%) | 58 (46.0%) |
| Age (yrs.) | |||
| Median (IQR) | 58 (49–65) | 58 (49–65) | 57 (49–64) |
| ≥65 | 92 (25.8%) | 61 (26.5%) | 31 (24.6%) |
| <65 | 264 (74.2%) | 169 (73.5%) | 95 (75.4%) |
| KPS | |||
| Median (IQR) | 80 (70–80) | 80 (70–80) | 80 (70–90) |
| ≥70 | 280 (78.7%) | 181 (78.7%) | 99 (78.6%) |
| <70 | 76 (21.3%) | 49 (21.3%) | 27 (21.4%) |
| Primary tumor | |||
| NSCLC | 268 (75.3%) | 170 (73.9%) | 98 (77.8%) |
| Breast cancer | 38 (10.7%) | 26 (11.3%) | 12 (9.5%) |
| Digestive system cancer | 23 (6.5%) | 15 (6.5%) | 8 (6.3%) |
| Others | 27 (7.6%) | 19 (8.3%) | 8 (6.3%) |
| Mutation status | |||
| NSCLC mutant | 146 (41.0%) | 90 (39.1%) | 56 (44.4%) |
| NSCLC wild type/unknown | 122 (34.3%) | 79 (34.3%) | 43 (34.1%) |
| N.A. (non-NSCLC) | 88 (24.7%) | 61 (26.5%) | 27 (21.4%) |
| Systemic disease control | |||
| Controlled | 146 (41.0%) | 97 (42.2%) | 50 (39.7%) |
| Uncontrolled | 210 (59.0%) | 134 (58.3%) | 76 (60.3%) |
| Number of BM | |||
| Solitary | 97 (27.2%) | 65 (28.3%) | 32 (25.4%) |
| Multiple | 259 (72.8%) | 165 (71.7%) | 94 (74.6%) |
| Distribution of BM | |||
| Supratentorial | 166 (46.6%) | 108 (47.0%) | 58 (46.0%) |
| Infratentorial | 34 (9.6%) | 21 (9.1%) | 13 (10.3%) |
| Both | 156 (43.8%) | 99 (43.0%) | 57 (45.2%) |
| Diameter of largest tumor (cm) | |||
| Median (IQR) | 2.7 (1.7–3.9) | 2.7 (1.8–3.9) | 2.7 (1.7–3.9) |
| ≥2.5 | 197 (55.3%) | 128 (55.7%) | 69 (54.8%) |
| <2.5 | 159 (44.7%) | 102 (44.3%) | 57 (45.2%) |
| Largest tumor volume (cm3) | |||
| Median (IQR) | 6.2 (1.6–15.4) | 6.3 (1.7–15.5) | 6.1 (1.6–15.3) |
| ≥2.5 | 241 (67.7%) | 156 (67.8%) | 85 (67.5%) |
| <2.5 | 115 (32.3%) | 74 (32.2%) | 41 (32.5%) |
| Cumulative tumor volume (cm3) | |||
| Median (IQR) | 9.5 (2.3–21.5) | 9.5 (2.4–21.0) | 9.5 (2.3–22.2) |
| ≥3.5 | 242 (68.0%) | 156 (67.8%) | 86 (68.3%) |
| <3.5 | 114 (32.0%) | 74 (32.2%) | 40 (31.7%) |
| SRS/FSRS | |||
| Single SRS | 189 (53.1%) | 125 (54.3%) | 64 (50.8%) |
| FSRS | 167 (46.9%) | 105 (45.7%) | 62 (49.2%) |
| BED (Gy) | |||
| Median (IQR) | 41.6 (41.6–50.4) | 43.2 (41.6–50.4) | 41.6 (41.6–50.4) |
| LDH (U/L) | |||
| Median (IQR) | 197 (167–249) | 197 (167–247) | 201 (167–257) |
| <200 | 181 (50.8%) | 119 (31.3%) | 62 (49.2%) |
| 200–300 | 122 (34.3%) | 77 (22.6%) | 45 (35.7%) |
| >300 | 53 (14.9%) | 34 (9.6%) | 19 (15.1%) |
KPS, Karnofsky Performance Score; N.A., not applicable; NSCLC, non-small cell lung cancer; BM, brain metastases; IQR, interquartile range; SRS, stereotactic radiosurgery; FSRS, fractionated stereotactic radiosurgery; BED, biologically effective dose; LDH, lactate dehydrogenase.