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Dose constraints for critical structures (treatment in 3–5 fractions).
| Critical structures | Dose constraints |
|---|---|
| Spinal cord | V18 < 1 mL |
| max20 Gy | |
| Lungs (right + left) | V5 < 40% |
| V10 < 20% | |
| Heart | V20 < 15 cm3 |
| max30 Gy | |
| Oesophagus | V25 < 1 mL |
| Remaining healthy liver | V15 < 30% |
| (Vtotal − V15) > 700 cm3 | |
| Stomach | V25 < 1 mL |
| Intestines | V27 < 1 mL |
| Kidneys | V15 < 30% |
