Saifi O, Pinnix CC, Ballas LK, Kelsey CR, Milgrom SA, Terezakis SA, Figura NB, Parikh RR, Grecula JC, Flampouri S, Ha CS, Lo AC, Plastaras JP, Hodgson DC, and Hoppe BS
Contemporary lymphoma radiation target volumes that rely on post-systemic therapy imaging do not have standardised nomenclature. A forum of radiation oncology lymphoma leaders from the National Clinical Trials Network groups (NRG Oncology, Children's Oncology Group, SWOG Cancer Research Network, Alliance for Clinical Trials in Oncology, Eastern Cooperative Oncology Group-American College of Radiology Imaging Network Cancer Research Group, and the Canadian Cancer Trials Group) was convened and established standardised nomenclature for these volumes in the autumn of 2024. Involved-site radiotherapy includes the full cranial-caudal extent of prechemotherapy disease and takes into account axial anatomical changes only. Residual site radiotherapy targets only the postchemotherapy CT-anatomical mass. PET-directed radiotherapy exclusively targets PET-positive disease and includes three types: PET-directed involved site radiotherapy using the superior-inferior aspect of prechemotherapy involved disease sites that remain PET-avid on post-treatment imaging; PET-directed residual site radiotherapy using only the postchemotherapy CT-anatomical residual mass that contains the PET-avid lesion on post-treatment imaging, without excluding sites that had complete metabolic response; and PET-directed residual PET radiotherapy using only the PET-avid focus, irrespective of the corresponding adjacent non-PET-avid CT-anatomical disease surrounding it., Competing Interests: Declaration of interests LKB declares (in the last 36 months) payment or honoraria for lectures, presentations, speakers, bureaus, manuscript writing, or educational events as visiting professor at University of Pittsburgh and Columbia University; leadership or fiduciary role in other board, society, committee, or advocacy group, paid or unpaid, for the American Board of Radiology as Oral Boards chair Hematology. SF declares (in the last 36 months) payment or honoraria for lectures, presentations, speakers, bureaus, manuscript writing, or educational events as visiting professor at University of Kansas; participation on the Proton Collaborative Group Data Safety Monitoring Board; leadership or fiduciary role in other board, society, committee, or advocacy group, paid or unpaid, as chair of Task Group Number 427 Technical Guidelines for the Use of Proton Therapy in Clinical Trials, for the American Association of Physicists in Medicine. JCG reports (without time limit) research in this publication was supported by the National Cancer Institute of the US National Institutes of Health, under award number U10CA180821 (to the Alliance for Clinical Trials in Oncology). JCG declares (in the last 36 months) grants or contracts from Intra-op Medical as institutional support for clinical trial; honorarium payments from DAVA Oncology and Primo-Oncology; support for travel paid by Alliance for Clinical Trials in Oncology to attend their group meeting as the Publication Committee co-chair; leadership or fiduciary role in other board, society, committee, or advocacy group, paid or unpaid, as Publications Committee co-chair at Alliance for Clinical Trials in Oncology, president and immediate past president, and a member of the board of directors at the International Society of Intraoperative Radiation Therapy, president and past president; is a councillor at the Ohio Radiological Society, Small Cell Lung Cancer Guideline, and a committee member at National Comprehensive Cancer Network. CSH declares (in the last 36 months) leadership or fiduciary role in other board, society, committee, or advocacy group, paid or unpaid, as chair of the Radiation Oncology Committee at SWOG since June, 2023. BSH declares (in the last 36 months) leadership or fiduciary role in other board, society, committee, or advocacy group, unpaid, as NRG Hematologic Working Group co-chair; and travel support to semi-annual meetings from the Children's Oncology Group. SAM declares (in the last 36 months) support for travel to Children's Oncology Group meetings paid for by the Children's Oncology Group, and travel to a National Comprehensive Cancer Network guidelines meeting paid for by the National Comprehensive Cancer Network; leadership or fiduciary role in other board, society, committee, or advocacy group, unpaid, as Children's Oncology Group Hodgkin Lymphoma Committee radiation oncology/imaging lead, American Radium Society Appropriate Use Criteria–Lymphoma chair, and a member of the International Journal of Radiation Oncology, Biology, Physics editorial board. All other authors declare no competing interests., (Copyright © 2024 Elsevier Ltd. All rights reserved, including those for text and data mining, AI training, and similar technologies.)