Table 3.
Maximum deliverable dose for each patient when designing treatment plans following the isotoxic trial protocol without maximum target dose cap. Plans were designed for the conventional linac or the MR-Linac, with either standard or reduced PTV margins. The respective constraints limiting further target dose escalation, either mean lung dose (lung) or maximum mediastinal envelope dose (med env) are also shown. Statistical significance was measured using a paired t-test.
| Patient number | Conventional linac (standard margins) |
MR-Linac (standard margins) |
MR-Linac (reduced margins) |
|||
|---|---|---|---|---|---|---|
| CTV dose [Gy] | Limiting constraint | CTV dose [Gy] | Limiting constraint | CTV dose [Gy] | Limiting constraint | |
| 1 | 81.0 | lung | 79.2 | lung | 86.4 | med env |
| 2 | 77.4 | lung | 75.6 | lung | 79.2 | lung |
| 3 | 86.4 | lung | 81.0 | lung | 93.6 | lung |
| 4 | 79.2 | med env | 77.4 | med env | 79.2 | med env |
| 5 | 73.8 | lung | 75.6 | lung | 75.6 | lung |
| 6 | 82.8 | med env | 81.0 | med env | 81.0 | med env |
| 7 | 81.0 | lung | 81.0 | lung | 82.8 | med env |
| 8 | 73.8 | med env | 73.8 | med env | 73.8 | med env |
| 9 | 77.4 | lung | 77.4 | lung | 79.2 | lung |
| 10 | 77.4 | lung | 77.4 | lung | 81.0 | lung |
| Mean | 79.0 | 78.8 | 81.2 | |||
| Significance level | 0.75 | 0.03 | ||||