Table 2.
Dose-volume parameters according to radiotherapy techniques
| Variable | 3D-CRT (n=48) | IMRT (n=29) | p-value |
|---|---|---|---|
| CTV (cm3) | 279.3 (89.4-1,543.3) | 357.5 (89.3-762.7) | 0.706 |
| CTV | |||
| < 300 cm3 | 28 (59.3) | 10 (34.5) | 0.043 |
| ≥ 300 cm3 | 20 (41.7) | 19 (65.5) | |
| Total lung | |||
| Mean dose (Gy) | 18.4 (9.3-28.0) | 19.6 (14.6-25.2) | 0.031 |
| V5 (%) | 57.2 (29.8-72.9) | 65.1 (48.4-90.0) | < 0.001 |
| V10 (%) | 48.6 (24.5-63.5) | 51.8 (41.8-62.9) | 0.107 |
| V15 (%) | 40.6 (18.1-54.5) | 42.3 (34.7-53.6) | 0.052 |
| V20 (%) | 32.8 (14.3-50.0) | 35.6 (28.2-45.9) | 0.061 |
| Esophagus | |||
| Maximum dose (Gy) | 67.1 (55.3-74.7) | 68.4 (60.0-77.3) | 0.007 |
| Mean dose (Gy) | 33.2 (12.5-55.8) | 35.1 (16.1-52.0) | 0.111 |
| V30 (%) | 52.1 (15.2-87.7) | 55.9 (15.8-79.6) | 0.520 |
| V45 (%) | 44.2 (3.7-74.9) | 48.8 (1.2-76.5) | 0.526 |
| Spinal cord | |||
| Maximum dose (Gy) | 43.9 (10.5-57.4) | 43.1 (32.3-48.4) | 0.708 |
| Heart | |||
| Median dose (Gy) | 8.6 (0.5-42.4) | 16.4 (1.5-35.0) | 0.001 |
Values are presented as median (range) or number (%). 3D-CRT, three-dimensional conformal radiotherapy; IMRT, intensity-modulated radiotherapy; CTV, clinical target volume; VD, percentage volume of organ receiving ≥ D Gy.