Sara R Alcorn1, Michael J Chen2, Line Claude3, Karin Dieckmann4, Ralph P Ermoian5, Eric C Ford6, Claude Malet3, Shannon M MacDonald7, Alexey V Nechesnyuk8, Kristina Nilsson9, Rosangela C Villar10, Brian A Winey7, Erik J Tryggestad11, Stephanie A Terezakis12. 1. Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins School of Medicine, Baltimore, Maryland. 2. Department of Radiation, Grupo de Apoio ao Adolescente e à Criança com Câncer, São Paulo, Brazil. 3. Département de Radiothérapie, Centre de Lutte Contre Le Cancer Léon Bérard, Lyon, France. 4. Department of Radiation Oncology, Universität Klinik Für Strahlentherapie und Strahlenbiologie, Vienna, Austria. 5. Department of Radiation Oncology, University of Washington, Seattle, Washington. 6. Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins School of Medicine, Baltimore, Maryland; Department of Radiation Oncology, University of Washington, Seattle, Washington. 7. Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts. 8. Department of Radiotherapy, Federal Scientific Clinical Center of Children's Hematology, Oncology and Immunology, Moscow, Russia. 9. Department of Oncology, Uppsala University Hospital, Uppsala, Sweden. 10. Department of Radiation Oncology Centro Infantil Boldrini, São Paulo e Região, Brazil. 11. Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins School of Medicine, Baltimore, Maryland; Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota. 12. Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins School of Medicine, Baltimore, Maryland. Electronic address: sterezak@jhmi.edu.
Abstract
PURPOSE: Image guided radiation therapy (IGRT) has become common practice for both photon and proton radiation therapy, but there is little consensus regarding its application in the pediatric population. We evaluated clinical patterns of pediatric IGRT practice through an international pediatrics consortium comprised of institutions using either photon or proton radiation therapy. METHODS AND MATERIALS: Seven international institutions with dedicated pediatric expertise completed a 53-item survey evaluating patterns of IGRT use in definitive radiation therapy for patients ≤21 years old. Two institutions use proton therapy for children and all others use IG photon therapy. Descriptive statistics including frequencies of IGRT use and means and standard deviations for planning target volume (PTV) margins by institution and treatment site were calculated. RESULTS: Approximately 750 pediatric patients were treated annually across the 7 institutions. IGRT was used in tumors of the central nervous system (98%), abdomen or pelvis (73%), head and neck (100%), lung (83%), and liver (69%). Photon institutions used kV cone beam computed tomography and kV- and MV-based planar imaging for IGRT, and all proton institutions used kV-based planar imaging; 57% of photon institutions used a specialized pediatric protocol for IGRT that delivers lower dose than standard adult protocols. Immobilization techniques varied by treatment site and institution. IGRT was utilized daily in 45% and weekly in 35% of cases. The PTV margin with use of IGRT ranged from 2 cm to 1 cm across treatment sites and institution. CONCLUSIONS: Use of IGRT in children was prevalent at all consortium institutions. There was treatment site-specific variability in IGRT use and technique across institutions, although practices varied less at proton facilities. Despite use of IGRT, there was no consensus of optimum PTV margin by treatment site. Given the desire to restrict any additional radiation exposure in children to instances where the exposure is associated with measureable benefit, prospective studies are warranted to optimize IGRT protocols by modality and treatment site.
PURPOSE: Image guided radiation therapy (IGRT) has become common practice for both photon and proton radiation therapy, but there is little consensus regarding its application in the pediatric population. We evaluated clinical patterns of pediatric IGRT practice through an international pediatrics consortium comprised of institutions using either photon or proton radiation therapy. METHODS AND MATERIALS: Seven international institutions with dedicated pediatric expertise completed a 53-item survey evaluating patterns of IGRT use in definitive radiation therapy for patients ≤21 years old. Two institutions use proton therapy for children and all others use IG photon therapy. Descriptive statistics including frequencies of IGRT use and means and standard deviations for planning target volume (PTV) margins by institution and treatment site were calculated. RESULTS: Approximately 750 pediatric patients were treated annually across the 7 institutions. IGRT was used in tumors of the central nervous system (98%), abdomen or pelvis (73%), head and neck (100%), lung (83%), and liver (69%). Photon institutions used kV cone beam computed tomography and kV- and MV-based planar imaging for IGRT, and all proton institutions used kV-based planar imaging; 57% of photon institutions used a specialized pediatric protocol for IGRT that delivers lower dose than standard adult protocols. Immobilization techniques varied by treatment site and institution. IGRT was utilized daily in 45% and weekly in 35% of cases. The PTV margin with use of IGRT ranged from 2 cm to 1 cm across treatment sites and institution. CONCLUSIONS: Use of IGRT in children was prevalent at all consortium institutions. There was treatment site-specific variability in IGRT use and technique across institutions, although practices varied less at proton facilities. Despite use of IGRT, there was no consensus of optimum PTV margin by treatment site. Given the desire to restrict any additional radiation exposure in children to instances where the exposure is associated with measureable benefit, prospective studies are warranted to optimize IGRT protocols by modality and treatment site.
Authors: Sara R Alcorn; Xian Chiong Zhou; Casey Bojechko; Rodrigo A Rubo; Michael J Chen; Karin Dieckmann; Ralph P Ermoian; Eric C Ford; Daria Kobyzeva; Shannon M MacDonald; Todd R McNutt; Alexey Nechesnyuk; Kristina Nilsson; Hakan Sjostrand; Koren S Smith; Markus Stock; Erik J Tryggestad; Rosangela C Villar; Brian A Winey; Stephanie A Terezakis Journal: Technol Cancer Res Treat Date: 2020 Jan-Dec