Table 3 Surface dose by means of in vivo Gafchromic film dosimetry and calculated skin dose in dependence of the PTV and radiation technique
Surface dose† | Calculated skin dose* | |||||||
|---|---|---|---|---|---|---|---|---|
Film position | ||||||||
Radiation technique | Central | Medial | Lateral | |||||
PTV | Mean | SD | Mean | SD | Mean | SD | Mean | SD |
Patient series 1: 3D-CRT versus TB-IMRT | ||||||||
Whole breast | ||||||||
3D-CRT | 53.8 | 6.0 | 42.2 | 5.0 | 48.5 | 7.1 | 91.8 | 13.3 |
TB-IMRT | 53.4 | 5.4 | 41.2 | 6.5 | 49.1 | 8.4 | 90.8 | 8.7 |
Difference (%) | -0.7 | -2.4 | 1.2 | -1.1 | ||||
p-value* | n.s. | n.s. | n.s. | n.s. | ||||
Chest wall | ||||||||
3D-CRT | 58.1 | 5.7 | 47.2 | 9.0 | 49.8 | 5.1 | 92.2 | 6.0 |
TB-IMRT | 58.3 | 6.3 | 45.4 | 7.9 | 51.9 | 6.2 | 92.0 | 8.8 |
Difference (%) | 0.3 | -3.8 | 4.2 | -0.2 | ||||
p-value* | n.s. | n.s. | n.s. | n.s. | ||||
Patient series 2: TB-IMRT versus 7 F-IMRT | ||||||||
Whole breast | ||||||||
TB-IMRT | 54.0 | 3.9 | 45.0 | 5.6 | 41.7 | 4.5 | 86.8 | 6.9 |
7 F-IMRT | 45.6 | 2.3 | 43.6 | 7.0 | 35.8 | 7.4 | 80.6 | 10.8 |
Difference (%) | -15.6 | -3.1 | -14.1 | -7.1 | ||||
p-value* | <0.01 | n.s. | 0.05 | 0.03 | ||||
Chest wall | ||||||||
TB-IMRT | 60.1 | 5.3 | 39.4 | 12.0 | 59.2 | 3.5 | 95.2 | 2.3 |
7 F-IMRT | 53.0 | 5.9 | 38.2 | 17.6 | 48.1 | 8.4 | 90.5 | 2.0 |
Difference (%) | -11.8 | -3.0 | -18.8 | -4.9 | ||||
p-value* | 0.02 | n.s. | 0.05 | <0.01 | ||||