Feasibility of reduced setup uncertainty in intensity-modulated proton therapy for mediastinal lymphoma.
[BACKGROUND AND PURPOSE] Mediastinal lymphoma patients are typically young and are at risk of long-term radiation-induced adverse events, making organ of interest (OOI) sparing a key objective of radi
- p-value p < 0.01
APA
Pisciotta P, Hengeveld A, et al. (2026). Feasibility of reduced setup uncertainty in intensity-modulated proton therapy for mediastinal lymphoma.. Physics and imaging in radiation oncology, 38, 100953. https://doi.org/10.1016/j.phro.2026.100953
MLA
Pisciotta P, et al.. "Feasibility of reduced setup uncertainty in intensity-modulated proton therapy for mediastinal lymphoma.." Physics and imaging in radiation oncology, vol. 38, 2026, pp. 100953.
PMID
41939505
Abstract
[BACKGROUND AND PURPOSE] Mediastinal lymphoma patients are typically young and are at risk of long-term radiation-induced adverse events, making organ of interest (OOI) sparing a key objective of radiotherapy. This study investigated whether reducing setup uncertainty during robust intensity-modulated proton therapy (IMPT) planning is feasible without compromising target coverage and delivered dose robustness.
[MATERIALS AND METHODS] Ten consecutive mediastinal lymphoma patients treated with IMPT were retrospectively analyzed. Treatment plans were generated on the four-dimensional average computed tomography (4DCT) using a 5 mm setup uncertainty (clinical standard). Additional plans with 4 and 3 mm setup uncertainties were created using a dose-mimicking optimization approach while maintaining identical clinical priorities. Robustness was evaluated using a three-dimensional robustness evaluation method (3DREM) and a longitudinal four-dimensional robustness evaluation method (4DREM), incorporating setup and range variations, machine uncertainties, respiratory motion, and weekly anatomical changes.
[RESULTS] All plans achieved adequate target coverage in the 3D-nominal and 4DREM voxel-wise mean dose distributions (V > 99.6 %). The voxel-wise minimum dose distributions from 4DREM confirmed robust target coverage (V > 98 %, D > 95 % of prescription dose) for all setup uncertainties, with one clinically accepted exception. Reducing setup uncertainty resulted in statistically significant reductions in organs of interest doses (p < 0.01), corresponding to median reductions in predicted lifetime acute coronary event risk of 0.17 % and 0.32 % for 4 mm and 3 mm setup uncertainties, respectively (p < 0.01).
[CONCLUSION] Reducing setup uncertainty during robust IMPT planning for mediastinal lymphoma patients was feasible and improved OOI sparing without compromising delivered dose robustness.
[MATERIALS AND METHODS] Ten consecutive mediastinal lymphoma patients treated with IMPT were retrospectively analyzed. Treatment plans were generated on the four-dimensional average computed tomography (4DCT) using a 5 mm setup uncertainty (clinical standard). Additional plans with 4 and 3 mm setup uncertainties were created using a dose-mimicking optimization approach while maintaining identical clinical priorities. Robustness was evaluated using a three-dimensional robustness evaluation method (3DREM) and a longitudinal four-dimensional robustness evaluation method (4DREM), incorporating setup and range variations, machine uncertainties, respiratory motion, and weekly anatomical changes.
[RESULTS] All plans achieved adequate target coverage in the 3D-nominal and 4DREM voxel-wise mean dose distributions (V > 99.6 %). The voxel-wise minimum dose distributions from 4DREM confirmed robust target coverage (V > 98 %, D > 95 % of prescription dose) for all setup uncertainties, with one clinically accepted exception. Reducing setup uncertainty resulted in statistically significant reductions in organs of interest doses (p < 0.01), corresponding to median reductions in predicted lifetime acute coronary event risk of 0.17 % and 0.32 % for 4 mm and 3 mm setup uncertainties, respectively (p < 0.01).
[CONCLUSION] Reducing setup uncertainty during robust IMPT planning for mediastinal lymphoma patients was feasible and improved OOI sparing without compromising delivered dose robustness.