Introduction
Methods and materials
Dosimetric compliance criteria for RTOG 1308 trial
RT Parameter | Per protocol | Variation acceptable |
---|---|---|
% of PTV covered by prescription dose | 95 % | ≥95 % of the PTV is covered by ≥95 % of the prescription dose |
% of ITV (motion-incorporated CTV) | 100 % | ≥99 % |
Maximum PTV dose PTV (0.03 cc) | ≤120 % RX | ≤125 % RX |
Minimum PTV dose (0.03 cc) | ≥85 % RX | ≥75 % RX |
Normal lung (Both lungs minus GTV) | V5 ≤ 60 % | V5 ≤ 65 % |
V20 ≤ 37 % | V20 ≤ 40 % | |
Mean dose < 20 Gy (RBE) | Mean Dose: ≤ 22 Gy (RBE) | |
Esophagus | Max dose: 74 Gy (RBE) ≤ 1 cc of partial circumference | Max dose: 74 Gy (RBE) ≤ 1.5 cc of partial circumference |
Brachial Plexus | V66 ≤ 2.0 cc | V66 ≤ 2.5 cc |
V70 ≤ 1.0 cc | V70 ≤ 1.5 cc | |
V74 ≤ 0.5 cc | V74 ≤ 1.0 cc | |
V75 ≤ 0.1 cc | V75 ≤ 0.5 cc | |
Spinal Cord | V50 < 0.03 cc | V52 < 0.03 cc |
Heart | V30 ≤ 50 % | 50 % ≤ V30 ≤ 55 % |
V45 ≤ 35 % | 35 % ≤ V45 ≤ 40 % |
Target definitions and treatment planning
Structure | Minimum | Maximum | Median | Mean ± SE |
---|---|---|---|---|
Target volume | 76.55 | 1160.83 | 420.5 | 548 ± 60 |
Normal Lung | 1328.66 | 5701.44 | 2860.8 | 3033 ± 183 |
Heart | 396.54 | 1084.13 | 676.96 | 671 ± 37 |
Esophagus | 21.59 | 66.97 | 33.73 | 35 ± 2 |
Spinal Cord | 14.25 | 71.59 | 37.95 | 39 ± 3 |
Quality assurance of treatment plans using knowledge-based engineering tool
Data analysis
Results
Quality assurance of photon IMRT plans using knowledge-based engineering tool
Dosimetric Criteria | Treatment planning system | Knowledge based engineering tool |
---|---|---|
Spinal Cord Maximum Dose (Gy) | 40 ± 2 | 44 ± 2 |
Esophagus Maximum Dose (Gy) | 68 ± 3 | 75 ± 2 |
Heart V30 Gy (%) | 16 ± 4 | 15 ± 3 |
Heart V45 Gy (%) | 10 ± 3 | 9 ± 2 |
Lung V20Gy (%) | 27 ± 2 | 29 ± 2 |
Lung mean dose (Gy) | 17 ± 1 | 18 ± 2 |
Compliance of IMRT and PSPT plans to RTOG 1308 dosimetric criteria
Structure | Dosimetric Parameter | Photon IMRT | Proton PSPT |
---|---|---|---|
% of cases failed to meet the criteria | % of cases failed to meet the criteria | ||
PTV | % of PTV covered by RX | 0 | 0 |
PTV minimum | 23 | 28 | |
PTV maximum | 0 | 4 | |
Spinal Cord | Maximum dose | 4 | 0 |
Total Lung (both lungs – GTV) | V5 | 4 | 0 |
V20 | 4 | 0 | |
Mean dose | 12 | 4 | |
Heart | V30 | 8 | 0 |
V45 | 4 | 0 | |
Brachial Plexus | V70 | 10 | 5 |
V74 | 10 | 0 | |
V75 | 5 | 0 |
Photon IMRT and proton PSPT dose volume histogram analysis
Structure | Photon IMRT | Proton PSPT | |||
---|---|---|---|---|---|
Median | Mean ± SE | Median | Mean ± SE | ||
PTV | % of PTV covered by RX | 95 | 95 | 95 | 95 |
PTV minimum | 57.0 | 56.7 ± 1.5 | 55.0 | 55.5 ± 1.4 | |
PTV maximum | 81.3 | 81.6. ± 0.7 | 79.9 | 80.9 ± 0.9 | |
Normal lung (total lungs – GTV) | Lung V5 | 42.6 | 47.2 ± 2.6 | 35.3 | 34.4. ± 1.6 |
Lung V20 | 27.9 | 28.1 ± 1.6 | 29.32 | 27.6 ± 1.5 | |
Mean Lung dose | 18.4 | 17.8 ± 0.9. | 18.3 | 16.4. ± 0.9. | |
Spinal cord | Spinal Cord maximum dose | 43.8 | 43.5 ± 1.4 | 37.9 | 31.7 ± 3.1 |
Heart | V5 | 39.4 | 47 ± 6 | 16.6 | 19. ± 3 |
V30 | 15.7 | 19 ± 4 | 9.7 | 11 ± 2 | |
V45 | 7.7 | 12.1 ± 2.7 | 7.4 | 7.8 ± 1.5 | |
V50 | 5.4 | 9.8. ± 2.3 | 6.5. | 7.1 ± 1.4 | |
V60 | 2.6 | 6.2 ± 1.5 | 4.2 | 6.7 ± 1.2 | |
V66 | 1.8 | 4.2 ± 1 | 2.9 | 4.7 ± 1.1 | |
Heart mean dose | 12.7 | 14.9 ± 2.4 | 6.7 | 7.7. ±1.4 | |
Maximum Dose | 78 | 69.3. ± 4.5 | 76.4 | 68.5. ± 4.4. | |
Esophagus | Mean dose | 20.1 | 22.7 ± 1.9 | 21.2 | 23 ± 2 |
Maximum dose | 76.2 | 73.2 ± 2.5 | 74.1 | 71. ± 3 | |
Brachial Plexus | V70 | 0 | 0.50 | 0 | 1.0 |
V74 | 0 | 0.27 | 0 | 0.10 | |
V75 | 0 | 0.18 | 0 | 0.11 |