Table 2.
Factors associated with testicular dose in univariate and multivariate analyses
| Continuous variables | Univariate analysis | Multivariate analysis | ||
|---|---|---|---|---|
| Coefficient [CI 95%] | p value | Coefficient [CI 95%] | p value | |
| Age | − 0.12 [− 0.31; 0.08] | 0.2 | ||
| Weight (kg) | − 0.45 [− 0.63; − 0.22] | < 0.001 | 0.002 [− 0.02; 0.02] | 0.915 |
| BMI (kg/m2) | − 0.37 [− 0.58; − 0.12] | 0.004 | − 0.04 [− 0.10; 0.02] | 0.213 |
| Physical dose to prostate (Gy) | − 0.40 [− 0.53; − 0.19] | < 0.001 | − 0.01 [− 0.07; 0.06] | 0.857 |
| Testicular volume (cc) | − 0.08 [− 0.27; 0.12] | 0.4 | ||
| Distance between inferior contour of CTV and testicle (mm) | − 0.62 [− 0.73; − 0.49] | < 0.001 | − 0.02 [− 0.02; − 0.01] | < 0.001 |
| Categorical variables | Mean physical dose to testicles (Gy) [CI 95%] | p value | OR [CI 95%] | p value |
|---|---|---|---|---|
| Technique | < 0.001 | 0.017 | ||
| Stereotactic radiotherapy (ref) | 0.18 [0.13; 0.23] | Ref | ||
| VMAT | 0.96 [0.64; 1.29] | 0.18 [− 1.87; 2.24] | ||
| Tomotherapy | 1.67 [1.24; 2.09] | 0.65 [− 1.46; 2.76] | ||
| Pelvic nodes irradiation | < 0.001 | 0.003 | ||
| No (ref) | 0.58 [0.27; 0.89] | Ref | ||
| Yes | 1.27 [1.01; 1.54] | 0.49 [0.18; 0.79] |
Bold indicates p value < 0.05 considered significant
CTV clinical target volume, VMAT volumetric modulated arc-therapy