Table 4.
Comparison of average and median Dmean of defined organs at risk (OARs) between volumetric modulated arc therapy (VMAT) and intensity modulated proton therapy (IMPT).
| Dmean of the OARs (Gy) | |||
|---|---|---|---|
| Average | Median | ||
| Oral Cavity | VMAT | 18.17 | 17.78 |
| IMPT | 5.40 | 4.48 | |
| Δdose | 12.76 | 12.67 | |
| p-value (VMAT vs. IMPT) | <.00001 | ||
| Larynx | VMAT | 11.56 | 8.78 |
| IMPT | 7.26 | 4.58 | |
| Δdose | 4.3 | 3.48 | |
| P value (VMAT vs. IMPT) | <.00001 | ||
| PCM | VMAT | 27.64 | 27.97 |
| IMPT | 17.34 | 17.31 | |
| Δdose | 10.30 | 10.43 | |
| P value (VMAT vs. IMPT) | <.00001 | ||
| Contralateral Parotid | VMAT | 6.65 | 6.26 |
| IMPT | 0,00 | 0,00 | |
| Δdose | 6.64 | 6.25 | |
| P value (VMAT vs. IMPT) | <.00001 | ||
| Contralateral Submandibular gland | VMAT | 8.31 | 8.94 |
| IMPT | 0.03 | 0 | |
| Δdose | 8.28 | 8.94 | |
| P value (VMAT vs. IMPT) | <.00001 | ||
| Supraglottic Larynx | VMAT | 16.05 | 15.95 |
| IMPT | 9.44 | 7.6 | |
| Δdose | 6.61 | 7.41 | |
| P value (VMAT vs. IMPT) | <.00001 | ||
| Ipsilateral Cochlea | VMAT | 33.20 | 28.12 |
| IMPT | 29.53 | 30.4 | |
| Δdose | 3.67 | 5.51 | |
| P value (VMAT vs. IMPT) | .01314 | ||
| Ipsilateral Inner ear | VMAT | 29.45 | 23.82 |
| IMPT | 25.18 | 23.05 | |
| Δdose | 4.27 | 6.003 | |
| P value (VMAT vs. IMPT) | .00252 | ||
Bold values denote statistical significance at the p < 0.05 level.