Robust Angle Selection in Particle Therapy

Abstract

The popularity of particle radiotherapy has grown exponentially over recent years owing to the marked advantage of the depth–dose curve and its unique biological property. However, particle therapy is sensitive to changes in anatomical structure, and the dose distribution may deteriorate. In particle therapy, robust beam angle selection plays a crucial role in mitigating inter- and intrafractional variation, including daily patient setup uncertainties and tumor motion. With the development of a rotating gantry, angle optimization has gained increasing attention. Currently, several studies use the variation in the water equivalent thickness to quantify anatomical changes during treatment. This method seems helpful in determining better beam angles and improving the robustness of planning. Therefore, this review will discuss and summarize the robust beam angles at different tumor sites in particle radiotherapy.

Dosimetric analysis of six whole-breast irradiation techniques in supine and prone positions

“…Arc-delivery PBT offers several benefits, including reduced calculation complexity and uncertainties, as well as optimization of high linear energy transfer deposition in tissues 53 . Arc-delivery PBT www.nature.com/scientificreports/ can be more robust than static-field PBT as range uncertainty is spread between different beam angles, and the RBE is increased within the target [53][54][55][56] . This approach has gained attention primarily due to the utilization of rotating gantries and spot-scanning techniques 54 .…”

“…Arc-delivery PBT www.nature.com/scientificreports/ can be more robust than static-field PBT as range uncertainty is spread between different beam angles, and the RBE is increased within the target [53][54][55][56] . This approach has gained attention primarily due to the utilization of rotating gantries and spot-scanning techniques 54 . In particular, spot-scanning proton arc (SPArc) can provide better target coverage and a significantly lower dose of OARs across various sites in comparison to IMPT 54,55 .…”

“…This approach has gained attention primarily due to the utilization of rotating gantries and spot-scanning techniques 54 . In particular, spot-scanning proton arc (SPArc) can provide better target coverage and a significantly lower dose of OARs across various sites in comparison to IMPT 54,55 .…”

Planning strategies for robust carbon-ion scanning radiotherapy for stage I esophageal cancer: a retrospective study

“…This finding could be ascribed to the effects of the heart and different gastric gas fills. The most robust irradiation angles for esophageal cancer are the anterior (0°) and posterior (180°) angles [ 36 ]. This is because the diaphragm is attached to the lumbar spine via the left and right cruciate tendons, and the posterior fan-shaped region containing the esophagus is relatively stationary with respect to diaphragmatic movement [ 37 ].…”

Value of carbon-ion radiotherapy for early stage non-small cell lung cancer

“…Some studies indicate that the tumor location is more effective than beam angle selection in early stage NSCLC, especially in patients with large tumors. However, in cases of locally advanced lung cancer, results differ in regard to affecting dose distribution of clinical target volume and organs at risk by selecting beam angles corresponding to the minimal WET change to compare with the original treatment plan [60] , [61] , [62] , [63] . In addition, in order to reduce insufficient dose coverage for clinical target volume and excessive irradiation for organs at risk, beam direction and angles should be considered due to the uncertainty of anatomical changes.…”