Table 2.
Volume | Pelvic RT | EFRT | ||||||
---|---|---|---|---|---|---|---|---|
HT | IMPT | IMRT | VMAT | HT | IMPT | IMRT | VMAT | |
OAR Parameters | ||||||||
Bowel V 10Gy (%) | 99.1 ± 1.3a,b,c | 52.4 ± 15.8d,e | 93.7 ± 4.1 | 94.6 ± 2.8 | 96.5 ± 4.3a | 40.3 ± 7.1d,e | 90.9 ± 6.6 | 94.0 ± 5.8 |
Bowel V 20Gy (%) | 74.8 ± 12.6a,c | 37.7 ± 13.3d,e | 73.7 ± 12.0 | 74.2 ± 3.1 | 61.9 ± 1.4a,c | 28.2 ± 7.0d,e | 60.6 ± 9.3 | 59.8 ± 8.5 |
Bowel V 30Gy (%) | 47.1 ± 18.8a,c | 28.4 ± 10.6d,e | 45.6 ± 12.9 | 44.8 ± 10.8 | 36.0 ± 10.6a,c | 18.2 ± 5.5d,e | 34.2 ± 8.5 | 32.7 ± 9.3 |
Bowel V 50Gy (%) | 6.7 ± 3.6 | 5.6 ± 2.1d,e | 11.8 ± 4.5 | 8.9 ± 2.5 | 6.5 ± 3.3a | 2.9 ± 0.9d,e | 8.8 ± 2.5 | 8.0 ± 2.8 |
Bowel D mean (Gy) | 27.6 ± 5.6a | 18.6 ± 5.9d,e | 30.2 ± 4.0 | 34.1 ± 7.0 | 24.0 ± 4.1a | 13.8 ± 2.8d,e | 26.3 ± 3.2 | 25.3 ± 3.7 |
Rectum D mean (Gy) | 47.8 ± 3.6a | 41.4 ± 5.3e | 47.2 ± 4.8 | 48.3 ± 1.6 | 48.2 ± 2.4a | 41.3 ± 3.0d,e | 48.5 ± 3.2 | 48.3 ± 1.5 |
Bladder D mean (Gy) | 49.2 ± 1.4a | 41.6 ± 5.8d,e | 49.1 ± 3.4 | 50.1 ± 1.6 | 48.4 ± 2.8a | 40.8 ± 6.4d,e | 49.5 ± 3.8 | 48.9 ± 2.3 |
PTV Parameters | ||||||||
HI PTV_A | 0.88 ± 0.02 | 0.87 ± 0.01 | 0.88 ± 0.01 | 0.87 ± 0.01 | 0.87 ± 0.01 | 0.87 ± 0.01 | 0.88 ± 0.01 | 0.88 ± 0.01 |
HI PTV_B | 0.94 ± 0.01a,b | 0.96 ± 0.01d,e | 0.92 ± 0.01f | 0.94 ± 0.01 | 0.94 ± 0.02a | 0.96 ± 0.01d,e | 0.93 ± 0.01 | 0.94 ± 0.01 |
CN PTV_A | 0.88 ± 0.03a,b | 0.92 ± 0.01d,e | 0.82 ± 0.02f | 0.88 ± 0.03 | 0.85 ± 0.13 | 0.88 ± 0.01d | 0.82 ± 0.06 | 0.88 ± 0.03 |
CN PTV_B | 0.87 ± 0.02 | 0.88 ± 0.05 | 0.84 ± 0.06 | 0.88 ± 0.03 | 0.86 ± 0.06a,c | 0.89 ± 0.03d | 0.78 ± 0.08 | 0.87 ± 0.08 |
CI PTV_A | 1.09 ± 0.05a,b,c | 1.03 ± 0.02d,e | 1.20 ± 0.03f | 0.98 ± 0.01 | 1.16 ± 0.07 | 1.05 ± 0.02d,e | 1.22 ± 0.11f | 0.97 ± 0.01 |
CI PTV_B | 1.07 ± 0.06 | 1.08 ± 0.07 | 1.16 ± 0.09f | 1.09 ± 0.05 | 1.15 ± 0.11 | 1.07 ± 0.06d | 1.24 ± 0.13f | 1.08 ± 0.10 |
HI: homogeneity index; CN: conformality number; CI: conformality index. VxGy: volume receiving at least x Gy. HT: helical tomotherapy; IMPT: intensity modulated proton therapy; IMRT: intensity modulated radiation therapy; VMAT: volumetric modulated arc therapy. EFRT: extended field radiation therapy. Statistical significance when p < 0.05. aHT vs IMPT; bHT vs IMRT; cHT vs VMAT; dIMPT vs IMRT; eIMPT vs VMAT; fIMRT vs VMAT.