Table 3.
Treatment characteristics stratified by fractionation regimen
| Total | Fractionation regimen | p value | |||||
|---|---|---|---|---|---|---|---|
| CF | HF | ||||||
| n | % | n | % | n | % | ||
| Fractionation regimen | |||||||
| 266 | 100.0 | 145 | 100.0 | 121 | 100.0 | ||
| Planning Target Volume (PTV) | |||||||
| Whole breast | 130 | 48.9 | 69 | 47.6 | 61 | 50.4 | 0.65 |
| Chest wall | 136 | 51.1 | 76 | 52.4 | 60 | 49.6 | |
| Locoregional lymph nodes treated as part of plan | |||||||
| Yes | 133 | 50.0 | 77 | 53.1 | 56 | 46.3 | 0.27 |
| No | 133 | 50.0 | 68 | 46.9 | 65 | 53.7 | |
| Boost to the PTV | |||||||
| Yes | 129 | 48.5 | 83 | 57.2 | 46 | 38.0 | <0.01 |
| No | 137 | 51.5 | 62 | 42.8 | 75 | 62.0 | |
| Radiation technique | |||||||
| 3DCRT | 115 | 43.2 | 73 | 50.3 | 42 | 34.7 | 0.01 |
| TB-IMRT | 151 | 56.8 | 72 | 49.7 | 79 | 65.3 | |
| Prolongation of the prescribed overall treatment time (days) | |||||||
| 0 | 220 | 82.7 | 103 | 71.0 | 117 | 96.7 | <0.001 |
| 1 | 20 | 7.5 | 18 | 12.4 | 2 | 1.7 | |
| 2 | 13 | 4.9 | 12 | 8.3 | 1 | 0.8 | |
| 3 | 6 | 2.3 | 5 | 3.4 | 1 | 0.8 | |
| 4 | 5 | 1.9 | 5 | 3.4 | 0 | 0 | |
| 5 | 2 | 08 | 2 | 1.4 | 0 | 0 | |
| Chemotherapy | |||||||
| Neo-adjuvant | 198 | 74.4 | 115 | 79.3 | 83 | 68.6 | 0.10 |
| Adjuvant | 56 | 21.1 | 26 | 17.9 | 30 | 24.8 | |
| No chemotherapy | 12 | 4.5 | 4 | 2.8 | 8 | 6.6 | |
| Hormone therapy | |||||||
| Yes | 198 | 74.7 | 111 | 76.6 | 87 | 72.5 | 0.45 |
| No | 67 | 25.3 | 34 | 23.4 | 33 | 27.5 | |
| Maximal radiation dermatitis grade (CTC v4.0)a | |||||||
| 0 | 20 | 7.5 | 7 | 4.8 | 13 | 10.7 | <0.001 |
| 1 | 216 | 81.2 | 110 | 75.9 | 106 | 87.6 | |
| 2 | 30 | 11.3 | 28 | 19.3 | 2 | 1.7 | |
| Time to dermatitis radiation grade 1 (days)a | |||||||
| Mean | 17 | 21 | 13 | <0.0001 | |||
| Standard deviation | 7 | 7 | 3 | ||||
| Time to dermatitis radiation grade 2 (days)a | |||||||
| Mean | 34 | 35 | 21 | <0.0001 | |||
| Standard deviation | 5 | 4 | 1 | ||||
Abbreviation: a = Skin reactions observed during the radiotherapy of the whole breast or chest wall (before the possible application of a boost to the PTV; for CF at the planned dose of 50.4 Gy or 50.0 Gy, for HF at the planned dose of 40.05 Gy)