Table 3.
Univariate and multivariable logistic regression analyses to determine associations with G3+L
| Univariate Regression Analysis | ||
|---|---|---|
| Variable | OR (95% CI) | P-value |
| Sex (Female) | 6.03 (2.24–17.89) | 0.001* |
| Age | 1.00 (0.96–1.04) | 0.89 |
| BMI | 0.92 (0.84–1.00) | 0.084 |
| GTV | 1.01 (0.99–1.02) | 0.246 |
| CTV | 1.00 (1.00–1.01) | 0.173 |
| PTV50 | 1.00 (1.00–1.01) | 0.146 |
| PTV60 | 1.00 (1.00–1.01) | 0.381 |
| Baseline ALC | 0.23 (0.08–0.57) | 0.003* |
| Baseline WBC | 1.06 (0.94–1.20) | 0.332 |
| Modality (photons) | 3.88 (1.29–14.56) | 0.025* |
| Preradiation steroids (yes) | 3.49 (1.20–11.14) | 0.026 |
| Location | ||
| Right | 0.79 (0.29–2.20) | 0.655 |
| Bilateral | 1.35 (0.06–15.67) | 0.815 |
| Whole brain DVH | ||
| Mean, Gy(RBE) | 1.00 (1.00–1.00) | 0.004* |
| V5 (%) | 1.03 (1.01–1.07) | 0.014* |
| V10 (%) | 1.04 (1.02–1.08) | 0.003* |
| V15 (%) | 1.04 (1.02–1.08) | 0.004* |
| V20 (%) | 1.06 (1.02–1.10) | 0.003* |
| V25 (%) | 1.06 (1.02–1.10) | 0.007* |
| V30 (%) | 1.06 (1.01–1.11) | 0.014* |
| V40 (%) | 1.06 (1.01–1.12) | 0.035* |
| V50 (%) | 1.06 (1.00–1.13) | 0.071 |
| Multivariate Regression Analysis | ||
| Variable | OR (95% CI) | P-value |
| Sex (Female) | 6.193 (1.951–22.37) | 0.0029 |
| Baseline ALC (K/µL) | 0.179 (0.052–0.511) | 0.0027 |
| Whole brain V20 (%) | 1.072 (1.028–1.125) | 0.0021 |
*Variables with statistically significant association.
Abbreviations: BMI, body mass index; GTV, gross tumor volume; CTV, clinical target volume; PTV-50 and PTV-60, planning target volumes receiving higher than 50 and 60 Gy respectively; DVH, dose-volume histogram; ALC, absolute lymphocyte count; WBC, white blood cells count (in units of 109 cells per liter); V5, V10, . . . , brain volumes receiving greater than 5, 10, . . . Gy(RBE) dose.