Table 3.
Univariate and Multivariate Logistic Regression of Factors Associated With LR After SBRT.
| Characteristic | OR (95% CI) | P |
|---|---|---|
| Univariate analysis | ||
| Age (<72 vs ≥72 years) | 0.547 (0.254 to 1.175) | .122 |
| Sex (female vs male) | 1.951 (0.865 to 4.402) | .107 |
| ECOG (0-1 vs 2) | 0.278 (0.639 to 1.435) | .278 |
| Smoker (No vs others) | 0.645 (0.337 to 1.232) | .184 |
| Underlying respiratory system disease (No vs others) | 0.475 (0.218 to 1.035) | .061 |
| Tumor diameter (<22.5 vs ≥22.5 mm) | 0.199 (0.084 to 0.476) | <.001 |
| Tumor location (Peripheral vs central) | 1.069 (0.467 to 2.449) | .874 |
| Pre-SBRT TLCs (<1600 vs ≥1600 cells/µL) | 0.201 (0.089 to 0.457) | <.001 |
| ATLCs (≥−350 vs <−350 cells/µL) | 0.042 (0.016 to 0.115) | <.001 |
| Post-SBRT TLCs (<1000 vs ≥1000 cells/µL) | 1.544 (0.719 to 3.317) | .265 |
| GTV (<8.2 vs ≥8.2 cm3) | 0.322 (0.147 to 0.702) | .004 |
| PTV (<32 vs ≥32 cm3) | 0.270 (0.116 to 0.629) | .002 |
| Lung V50 (<1 vs ≥1%) | 0.160 (0.069 to 0.372) | <.001 |
| Fractionation (50 Gy/5 fractions vs 60 Gy/10 fractions) | 0.245 (0.108 to 0.556) | .001 |
| Radiation time (<3950 vs ≥3950 s) | 0.097 (0.036 to 0.260) | <.001 |
| Multivariate analysis | ||
| Underlying respiratory system disease (No vs others) | 0.223 (0.066-0.760) | .016 |
| ATLCs (≥−350 vs <−350 cells/µL) | 0.045 (0.013-0.155) | <.001 |
| Lung V50 (<1 vs ≥1%) | 0.206 (0.059-0.714) | .013 |
| Radiation time (<3950 vs ≥3950 s) | 0.113 (0.029-0.432) | .001 |
Abbreviations: RL, lymphocyte recovery; SBRT, stereotactic body radiation therapy; OR, Odds ratio; CI, confidence interval; ECOG, Eastern Cooperative Oncology Group; TLCs, total lymphocyte counts; ATLC, alteration of TLCs; GTV, gross tumor volume; PTV, planning target volume; Lung V50, the percentage of total lung volume receiving at least 50 Gy.