Table 2.
Dosimetric comparison in OARs between sIMRT planning and conventional IMRT planning.
| OARs | IMRT | sIMRT | t | P value |
|---|---|---|---|---|
| Left-lung (n = 34) | ||||
| Dmean (Gy) | 13.2 ± 6.5 | 13.5 ± 7.2 | −1.503 | .142 |
| V5 (%) | 53.5 ± 16.6 | 51.0 ± 16.3 | 2.140 | .040* |
| V10 (%) | 40.8 ± 17.2 | 40.0 ± 17.2 | 0.650 | .520 |
| V15 (%) | 31.0 ± 16.0 | 31.9 ± 17.0 | −1.484 | .147 |
| V20 (%) | 23.3 ± 15.7 | 25.7 ± 16.4 | −2.617 | .013* |
| V25 (%) | 19.7 ± 14.9 | 21.2 ± 15.7 | −3.272 | .003* |
| V30 (%) | 16.3 ± 13.4 | 17.3 ± 14.6 | −2.180 | .036* |
| V35 (%) | 12.9 ± 11.6 | 13.9 ± 13.3 | −1.773 | .085 |
| V40 (%) | 9.7 ± 10.1 | 10.7 ± 11.5 | −2.329 | .026* |
| Right-lung (n = 34) | ||||
| Dmean (Gy) | 14.5 ± 7.9 | 14.4 ± 8.3 | 0.989 | .330 |
| V5 (%) | 53.9 ± 18.8 | 50.8 ± 19.6 | 2.500 | .018* |
| V10 (%) | 41.8 ± 19.3 | 40.0 ± 19.7 | 2.897 | .007* |
| V15 (%) | 33.6 ± 18.3 | 32.9 ± 18.7 | 1.420 | .165 |
| V20 (%) | 28.0 ± 16.5 | 27.5 ± 17.3 | 0.500 | .620 |
| V25 (%) | 22.3 ± 15.2 | 23.1 ± 15.7 | −1.384 | .176 |
| V30 (%) | 19.0 ± 14.2 | 19.1 ± 14.4 | −0.541 | .592 |
| V35 (%) | 15.4 ± 13.1 | 15.3 ± 13.2 | 0.110 | .913 |
| V40 (%) | 11.9 ± 12.0 | 12.0 ± 12.1 | −0.074 | .942 |
| Lungs (n = 34) | ||||
| Dmean (Gy) | 13.2 ± 2.8 | 13.1 ± 2.8 | 0.543 | .591 |
| V5 (%) | 52.4 ± 12.1 | 49.2 ± 10.0 | 3.195 | .003* |
| V10 (%) | 39.7 ± 9.3 | 38.2 ± 7.5 | 2.268 | .030* |
| V15 (%) | 30.6 ± 6.1 | 30.5 ± 6.1 | 0.466 | .644 |
| V20 (%) | 24.0 ± 4.6 | 24.8 ± 5.2 | −3.042 | .005* |
| V25 (%) | 19.7 ± 4.3 | 20.4 ± 4.5 | −3.274 | .002* |
| V30 (%) | 16.2 ± 4.1 | 16.7 ± 4.2 | −1.970 | .057 |
| V35 (%) | 12.9 ± 4.1 | 13.2 ± 4.1 | −0.934 | .357 |
| V40 (%) | 9.8 ± 4.2 | 10.1 ± 4.2 | −1.255 | .218 |
| Heart (n = 34) | ||||
| V25 (%) | 21.3 ± 16.4 | 21.8 ± 16.6 | −1.466 | .152 |
| V30 (%) | 17.4 ± 13.6 | 17.8 ± 13.7 | −1.239 | .224 |
| V35 (%) | 13.8 ± 11.2 | 14.3 ± 11.6 | −1.584 | .123 |
| V40 (%) | 10.3 ± 9.3 | 11.0 ± 9.9 | −2.401 | .022* |
| V45 (%) | 6.2 ± 6.5 | 7.5 ± 7.8 | −2.882 | .007* |
| Esophageal (n = 15) | ||||
| Dmean (Gy) | 29.2 ± 7.6 | 30.2 ± 7.4 | −2.972 | .010* |
| V50 (%) | 19.7 ± 21.2 | 20.9 ± 21.7 | −1.795 | .094 |
| Spinal-cord (n = 34) | ||||
| Dmax (Gy) | 37.7 ± 2.3 | 38.1 ± 3.5 | −1.012 | .319 |
| Dmean (Gy) | 13.8 ± 5.8 | 13.7 ± 5.8 | 0.808 | .425 |
Dmax = maximum dose, Dmean = mean dose, IMRT = intensity-modulated radiation therapy, sIMRT = simplified intensity-modulated radiation therapy, OAR = organs at risk, Vx = the percentage of the organs volume of receiving dose ≥ x Gy.
*
Represents significant statistical difference.