Table 2. Dosimetric parameters of axilla and organs at risk in s-IMRT versus for-IMRT plan.
| Structures | Parameters | Mean (95% CI) | P value | |
|---|---|---|---|---|
| S-IMRT plan | For-IMRT plan | |||
| Axillary levels | ||||
| Axillary level I | Dmean (Gy) | 27.7 (26.1~29.4) | 29.1 (27.2~31.0) | 0.011 |
| V47.5Gy (%) | 16.9 (14.1~20.0) | 27.6 (24.6~30.7) | < 0.001 | |
| V45Gy (%) | 22.1 (19.0~25.4) | 34.5 (31.0~38.1) | < 0.001 | |
| V40Gy (%) | 31.3 (28.0~35.1) | 41.1 (37.3~45.0) | < 0.001 | |
| Axillary level II | Dmean (Gy) | 10.6 (8.9~12.3) | 10.9 (9.2~12.6) | 0.403 |
| V47.5Gy (%) | 1.7 (0.8~2.9) | 1.8 (0.8~2.9) | 0.909 | |
| V45Gy (%) | 2.7 (1.5~4.4) | 4.4 (2.6~6.7) | 0.011 | |
| V40Gy (%) | 5.7 (3.9~8.0) | 8.3 (5.7~11.3) | 0.002 | |
| Axillary level III | Dmean (Gy) | 2.5 (2.1~3.1) | 2.8 (2.3~3.4) | 0.089 |
| V47.5Gy (%) | 0.0 (0.0~0.0) | 0.0 (0.0~0.0) | -- | |
| V45Gy (%) | 0.0 (0.0~0.0) | 0.1 (0.0~0.2) | 0.409 | |
| V40Gy (%) | 0.1 (0.0~0.2) | 0.2 (0.0~0.6) | 0.198 | |
| Organs at risk | ||||
| Ipsilateral lung | Dmean (Gy) | 8.5 (8.2~8.8) | 8.9 (8.5~9.2) | < 0.001 |
| V30Gy (%) | 10.6(10.0~11.3) | 13.5 (12.7~14.2) | < 0.001 | |
| V20Gy (%) | 14.7 (14.0~15.4) | 16.8 (15.9~17.6) | < 0.001 | |
| Heart | Dmean (Gy) | 4.1 (3.7~4.5) | 4.9 (4.3~5.5) | 0.001 |