Table 1.
Dosimetric parameters for TREAT planning target volume (PTV) coverage (without boost)
| Variable | Technique |
||||
|---|---|---|---|---|---|
| Conv | FIF-IMRT | HT-IMRT | TD-3DCRT | TD-IMRT | |
| Left PTV | |||||
| Max. (Gy) | 54.44 (0.90) | 53.13 (0.46) | 55.13 (2.87) | 57.84 (2.05) | 59.78 (3.03) |
| Min. (Gy) | 44.32 (2.04) | 39.48 (8.21) | 37.06 (4.38) | 33.23 (4.62) | 32.09 (6.61) |
| Mean (Gy) | 50.17 (0.60) | 49.77 (0.65) | 50.99 (0.78) | 48.77 (0.21) | 49.52 (0.64) |
| V90 (%) | 99.92 (0.11) | 98.77 (0.83) | 97.86 (2.05) | 99.82 (0.15) | 99.65 (0.29) |
| V95 (%) | 93.69 (6.78) | 92.23 (3.30) | 94.86 (3.75) | 94.46 (2.75) | 95.93 (3.21) |
| V107 (%) | 3.05 (3.06) | 0.17 (0.43) | 1.10 (1.43) | 1.20 (0.59) | 1.69 (1.14) |
| V110 (%) | 0.03 (0.78) | 0.00 (0.12) | 0.42 (0.13) | 0.43 (0.30) | 0.66(0.57) |
| HI | 12.98 (2.70) | 13.58 (5.16) | 15.49 (7.74) | 10.51 (2.29) | 10.32 (2.47) |
| Right PTV | |||||
| Max. (Gy) | 55.10 (0.72) | 53.17 (0.55) | 54.90 (2.85) | 57.94 (1.87) | 58.89 (2.56) |
| Min. (Gy) | 45.56 (3.28) | 40.37 (8.33) | 38.20 (3.45) | 36.01 (7.32) | 30.21 (8.96) |
| Mean (Gy) | 50.72 (0.71) | 49.88 (0.65) | 51.07 (0.90) | 48.70 (0.29) | 48.53 (3.43) |
| V90 (%) | 99.98 (0.01) | 99.40 (1.55) | 98.67 (1.36) | 99.88 (0.87) | 99.74 (0.20) |
| V95 (%) | 95.32 (6.14) | 94.20 (3.13) | 96.35 (2.85) | 95.03 (3.37) | 96.99 (1.95) |
| V107 (%) | 5.06 (4.10) | 0.15 (0.43) | 0.64 (1.10) | 0.97 (0.81) | 1.56 (1.67) |
| V110 (%) | 0.24 (0.34) | 0.00 (0.00) | 0.04 (0.11) | 0.21 (0.16) | 0.51 (0.45) |
| HI | 12.26 (2.26) | 13.46 (4.58) | 13.77 (6.53) | 9.37 (2.49) | 10.1 (2.35) |
| Conformity index | 1.36 (0.15) | 1.55 (0.42) | 1.27 (0.38) | 5.24 (2.46) | 2.11 (0.74) |
| Volume of body receiving 107% of prescribed dose (cm3) | 47.44 (28.79) | 1.58 (1.75) | 37.54 (100.59) | 80.38 (39.81) | 48.59 (38.30) |
3DCRT, three-dimensional conformal radiotherapy; conv., conventional; FIF, field in field; HI, homogeneity index; HT, helical tomotherapy; IMRT, intensity-modulated radiotherapy; max., maximum; min., minimum; SIB, simultaneous integrated boost; TD, TomoDirect™ (Accuray Inc., Sunnyvale, CA); TREAT PTV, term for volume common to reference volume and PTV; Vx, target volume receiving at least X% of prescribed dose.
The values in the table are expressed as mean (standard deviation).