Table 4.
Relevant plan parameters of 3D-CRT versus TB-IMRT or TB-IMRT versus 7 F-IMRT of the breast or chest wall
|
Organ |
Patient series 1: 3D-CRT versus TB-IMRT |
Patient series 2: TB-IMRT versus 7 F-IMRT |
||||||
|---|---|---|---|---|---|---|---|---|
| Factor | RT technique | Mean | 95% CI | p-value* | RT technique | Mean | 95% CI | p-value* |
| Skin | ||||||||
| Mean Dose (percent of the prescribed dose) | ||||||||
| |
3D-CRT |
92.0 |
(88.1; 95.9) |
n.s. |
TB-IMRT |
90.0 |
(85.8; 94.2) |
<0.01 |
| |
TB-IMRT |
91.4 |
(88.1; 94.8) |
|
7 F-IMRT |
84.4 |
(78.6; 90.3) |
|
| |
Difference (%) |
-0.7 |
|
|
Difference (%) |
-6.2 |
|
|
| PTV | ||||||||
| Homogeneity index | ||||||||
| |
3D-CRT |
0.73 |
(0.65; 0.80) |
n.s. |
TB-IMRT |
0.75 |
(0.68; 0.81) |
n.s. |
| |
TB-IMRT |
0.73 |
(0.67; 0.78) |
|
7 F-IMRT |
0.72 |
(0.63; 0.81) |
|
| |
Difference (%) |
0 |
|
|
Difference (%) |
-4.0 |
|
|
| Conformity index | ||||||||
| |
3D-CRT |
0.76 |
(0.71; 0.81) |
<0.001 |
TB-IMRT |
0.88 |
(0.85; 0.91) |
n.s. |
| |
TB-IMRT |
0.86 |
(0.82; 0.89) |
|
7 F-IMRT |
0.88 |
(0.85; 0.91) |
|
| |
Difference (%) |
13.2 |
|
|
Difference (%) |
0 |
|
|
| Heart (left-sided PTV) | ||||||||
| Mean Dose (cGy) | ||||||||
| |
3D-CRT |
506 |
(359; 654) |
n.s. |
TB-IMRT |
824 |
(423; 1224) |
0.01 |
| |
TB-IMRT |
504 |
(380; 628) |
|
7 F-IMRT |
1647 |
(937; 2357) |
|
| |
Difference (%) |
-0.4 |
|
|
Difference (%) |
99.9 |
|
|
| V70% |
|
|
|
|
|
|
|
|
| |
3D-CRT |
5.12 |
(2.49; 7.75) |
0.03 |
TB-IMRT |
9.25 |
(1.7; 16.8) |
n.s. |
| |
TB-IMRT |
2.57 |
(1.06; 4.09) |
|
7 F-IMRT |
10.00 |
(1.5; 18.5) |
|
| |
Difference (%) |
-49.8 |
|
|
Difference (%) |
8.1 |
|
|
| Heart (right-sided PTV) | ||||||||
| Mean Dose (cGy) | ||||||||
| |
3D-CRT |
157 |
(33; 282) |
n.s. |
TB-IMRT |
78 |
(60; 97) |
<0.001 |
| |
TB-IMRT |
149 |
(42; 282) |
|
7 F-IMRT |
704 |
(603; 805) |
|
| |
Difference (%) |
-5.1 |
|
|
Difference (%) |
802.6 |
|
|
| Ipsilateral lung | ||||||||
| Mean Dose (cGy) | ||||||||
| |
3D-CRT |
1276 |
(1179; 1374) |
<0.001 |
TB-IMRT |
1031 |
(842; 1221) |
<0.001 |
| |
TB-IMRT |
1036 |
(943; 1129) |
|
7 F-IMRT |
1535 |
(1382; 1689) |
|
| |
Difference (%) |
-18.8 |
|
|
Difference (%) |
48.9 |
|
|
| D60% |
|
|
|
|
|
|
|
|
| |
3D-CRT |
194 |
(174; 214) |
n.s. |
TB-IMRT |
139 |
(101; 177) |
<0.001 |
| |
TB-IMRT |
187 |
(168; 206) |
|
7 F-IMRT |
686 |
(458; 913) |
|
| |
Difference (%) |
-3.6 |
|
|
Difference (%) |
393.5 |
|
|
| D30% |
|
|
|
|
|
|
|
|
| |
3D-CRT |
1327 |
(1036; 1618) |
<0.001 |
TB-IMRT |
934 |
(535; 1334) |
<0.001 |
| |
TB-IMRT |
922 |
(725; 1119) |
|
7 F-IMRT |
1775 |
(1459; 2091) |
|
| |
Difference (%) |
-30.5 |
|
|
Difference (%) |
90.0 |
|
|
| Contralateral lung | ||||||||
| Mean Dose (cGy) | ||||||||
| |
3D-CRT |
27 |
(24; 31) |
n.s. |
TB-IMRT |
23 |
(18; 28) |
<0.001 |
| |
TB-IMRT |
26 |
(23; 29) |
|
7 F-IMRT |
328 |
(259; 397) |
|
| Difference (%) | -3.7 | Difference (%) | 1326.1 | |||||
Abbreviations:95% CI 95% confidence interval, Vx% percentage of tissue volume encompassed by the x% isodose line, Dx% dose to x% of the volume of the organ at risk, *Paired t-test, n.s. Not significant, other abbreviations: see Table 1.