Table 2.
Details of patients who underwent online adaptation for OAR constraint violation or to improve target coverage.
| OAR Constraint Violation | Hard Constraint | Violation Frequency | Violation % | |||
|---|---|---|---|---|---|---|
| Duodenum or small bowel | < 0.5 cc at 36 Gy | 94 / 495 | 19.0 | |||
| Stomach | < 0.5 cc at 36 Gy | 51 / 495 | 10.3 | |||
| Large bowel | < 0.5 cc at 36 Gy | 25 / 495 | 5.1 | |||
| Heart | < 15 cc at 32 Gy | 9 / 495 | 1.8 | |||
| Uninvolved liver | < 700 cc at 20 Gy < 33 % at 25 Gy |
2 / 495 | 0.4 | |||
| Esophagus | < 0.5 cc at 36 Gy | 1 / 495 | 0.2 | |||
| Kidneys | Mean < 18 Gy | 1 / 495 | 0.2 | |||
| Spinal cord | < 0.5 cc at 25 Gy | 0 / 495 | 0.0 | |||
| Target Coverage | N | Statistic | Pre-adaptation | Post-adaptation | Change in PTV Coverage (Δ) | P-value |
| PTV ≥ 95 % at 50 Gy | 39 | Median (IQR) | 87 (78 – 93) | 92 (81 – 97) | 3.8 (1.0 – 9.1) | <0.01 |
| Range | 41 – 98 | 36 – 100 | −4.6 – 20.8 | |||
| PTV ≥ 95 % at 47.5 Gy | 34 | Median (IQR) | 91 (82 – 96) | 95 (87 – 99) | 3.2 (1.3 – 5.2) | <0.01 |
| Range | 56 – 100 | 68 – 100 | −1.6 – 20.3 | |||
| PTV Optimized ≥ 95 % | 34 | Median (IQR) | 98 (95 – 100) | 98 (97 – 100) | 0.11 (-0.10 – 0.70) | 0.04 |
| at 47.5 Gy | Range | 56 – 100 | 53 – 100 | −5.1 – 15.9 | ||
1Statistical test performed: Wilcoxon signed rank test.
PTV, Planning Target Volume.