Table 3.
Summary of dosimetric results for SBRT planning study comparing 3DCRT versus IMRT versus VMAT–RA for the treatment of abdominal metastasis
| Reference | Bignardi et al.11 | Kumar et al.12 | |||
|---|---|---|---|---|---|
| Target area | Lymph nodes (abdominal region) 45 Gy/6Fx | Locally advanced pancreatic cancer | |||
| Dose/Fx | Plans acceptable if PTV dose >36 Gy (spinal cord 53 ± 21 cm3) (small bowel 780 ± 633 cm3) | 25 Gy/1Fx | |||
| Variable | 3DCRT | IMRT (co-planar) | VMAT RA | DS VMAT | DS IMRT |
| Patients | 14 | 15 | |||
| Effective treatment time (min) | 6.3 ± 0.5 | 10.6 ± 1.2 | 3.7 ± 0.4 | 9 | 11.45 |
| PTV: mean volume (cm3) | 44.0 ± 0.4 | 44.26 ± 0.4 | 44.5 ± 0.3 | 135 | 135 |
| PTV V95 (%) | 82.5 ± 9.6 | 84.5 ± 8.2 | 90.2 ± 5.2 | 97.5 | 98.6 |
| Healthy tissue V10Gy (%) | 6.3 ± 4.4 | 4.0 ± 1.9 | 3.1 ± 1.81 | NA | NA |
| Healthy tissue integral dose (Gy cm3 10−5) | NA | NA | NA | 0.37 | 0.35 |
| Healthy tissue CI60% | 3.8 ± 1.49 | 3.2 ± 0.7 | 2.5 ± 0.3 | NA | NA |
| Left kidney V5 Gy (%) | NA | NA | NA | 7.6 | 17.6 |
| Small bowel D1% (Gy) or D1cc (Gy) | D1% (Gy) 23.02 ± 10.81 | D1% (Gy) 19.01 ± 11.50 | D1% (Gy) 18.01 ± 10.83 | D1cc (Gy) 24.7 | D1cc (Gy) 25.6 |
| Small bowel V36Gy or V20 Gy (%) | V36Gy 0.3 ± 0.7 | V36Gy 0.2 ± 0.4 | V36Gy 0.1 ± 0.2 | V20 Gy 18.8 | V20 Gy 21.9 |
| Spinal cord Dmax (Gy) | 13.7 ± 5.7 | 13.9 ± 3.2 | 9.6 ± 2.3 | 11.6 | 11.7 |
| Spinal cord D1% (Gy) or V5 (Gy) | D1% (Gy) 12.9 ± 5.9 | D1% (Gy) 10 ± 2.8 | D1% (Gy) 7.8 ± 2.3 | V5 (Gy) 22.2 | V5 (Gy) 23.8 |
| Liver mean (Gy) | 4.3 ± 4.3 | 3.8 ± 4.0 | 3.6 ± 3.9 | 2.8 | 2.5 |
| MUs | 1554 ± 153 | 2583 ± 699 | 2186 ± 211 | 5437 | 6894 |
MU, monitor units; PTV, planning target volume; IMRT, intensity modulated radiotherapy; VMAT, volumetric modulated arc therapy; 3DCRT, 3D conformal radiotherapy therapy; RA, rapid arc; Dmax, maximum dose; SD, standard deviation; CI, conformity index; Fx, fraction; DS, dose sparing; Vn, volume of tissue receiving n dose (Gy); NA, not applicable; Dxx%, dose (Gy) to xx% of volume.