KEY POINTS
- This Medical Physics study introduced a single-field-each-peak optimization framework for proton LATTICE therapy, assigning each lattice peak to exactly 1 optimally selected proton field.
- The method was tested in 3 planning cases: abdomen with 3 peaks, lung with 6 peaks, and pancreas with 5 peaks.
- Compared with exhaustive-search plans, the new method maintained comparable plan quality while ensuring single-field delivery for each peak; peak conformity index was 1.00 for abdomen and pancreas and 0.98 for lung.
- Under standard robustness testing with 3.5% range uncertainty and 5 mm setup uncertainty, SFEP showed narrower peak DVH uncertainty bands than IMPT-based proton LATTICE.
- In the abdomen motion-shift test, peak coverage at 100% prescription dose decreased from 100% to 82.5% with SFEP versus 89.5% to 64.6% with IMPT.
CLINICAL TAKEAWAY
Single-field-each-peak optimization is a technically interesting way to reduce one of the weak points of proton LATTICE: motion-sensitive multi-field peak convergence. The study suggests better peak localization robustness than IMPT-based proton LATTICE in simulated abdomen, lung, and pancreas cases. But this remains an early planning feasibility study using simplified beam modeling and no machine-specific deliverability validation, so it is technical progress, not a clinically deployable workflow yet.