Abstract
PurposeTo evaluate the dosimetric differences between photon intensity‐modulated radiation therapy (IMRT) plans, 3D conformal proton therapy (3DCPT), and intensity‐modulated proton therapy (IMPT) plans and to investigate the dosimetric impact of different beam spot size and beam apertures in IMPT for pediatric Ewing sarcoma of the chest wall.Methods and MaterialsSix proton pediatric patients with Ewing sarcoma in the upper, middle, and lower thoracic spine regions as well as upper lumbar spine region were treated with 3DCPT and retrospectively planned with photon IMRT and IMPT nozzles of different beam spot sizes with/without beam apertures. The plan dose distributions were compared both on target conformity and homogeneity, and on organs‐at‐risk (OARs) sparing using QUANTEC metrics of the lung, heart, liver, and kidney. The total integral doses of healthy tissue of all plans were also evaluated.ResultsTarget conformity and homogeneity indices are generally better for the IMPT plans with beam aperture. Doses to the lung, heart, and liver for all patients are substantially lower with the 3DPT and IMPT plans than those of IMRT plans. In the IMPT plans with large spot without beam aperture, some OAR doses are higher than those of 3DCPT plans. The integral dose of each photon IMRT plan ranged from 2 to 4.3 times of proton plans.ConclusionCompared to IMRT, proton therapy delivers significant lower dose to almost all OARs and much lower healthy tissue integral dose. Compared to 3DCPT, IMPT with small beam spot size or using beam aperture has better dose conformity to the target.
Highlights
Childhood cancer accounts for less than 1% of all cancers diagnosed each year,[1] but it is the second leading cause of death in children between ages 1 and 14
Dosimetric comparisons were made between photon intensity‐modulated radiotherapy (IMRT), 3D conformal proton therapy (3DCPT), and intensity‐modulated proton therapy (IMPT) plans for six pediatric patients with posterior chest wall Ewing sarcomas
All the IMRT and pencil beam scanning (PBS) plans were scaled to the corresponding patient 3DCPT plan coverage
Summary
Childhood cancer accounts for less than 1% of all cancers diagnosed each year,[1] but it is the second leading cause of death in children between ages 1 and 14. | 101 about one third of all bone tumors in children.[2] Ewing sarcoma of the axial skeleton, for example base of skull, chest wall, and pelvis, is frequently treated with radiotherapy that serves as preoperative, definitive, or adjuvant therapy.[3,4,5,6,7] Due to the proximity of critical organs, radiotherapy is commonly associated with side effects and complications. This study was a clinical dosimetric study that compared the treatment techniques across widely used radiation modalities and technology representations to provide a realistic assessment of Ewing sarcoma treatment options
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
