LUNG STAGING IN PEDIATRIC HODGKIN LYMPHOMA: STAGING EVALUATION & RESPONSE CRITERIA HARMONIZATION FOR CHILDHOOD, ADOLESCENT & YOUNG ADULT HL (SEARCH FOR CAYAHL) CONSENSUS

Introduction: Staging of lung lesions in pediatric Hodgkin lymphoma (HL) is a long standing, controversial issue. Consortium groups define lung involvement and its distinction from E-lesions differently. Application of these criteria to individual patients are technically challenging and require expertise. The SEARCH group, working to create harmonization across consortia for the staging of pediatric HL, has completed this task for lung lesions. Methods: A survey of 7 case vignettes was distributed to 26 world experts in pediatric HL, replicating the previously published survey by Connors et al in 1984. Experts were asked to stage each case as lung involvement, or an E-lesion. Similar to Connors findings, our results demonstrated that experts were greatly divided on several cases, indicating ongoing differences in interpretation. Accordingly, the SEARCH group performed a harmonization initiative for the contemporary staging criteria for lung lesions. Representatives from each major consortium group (Pediatric Hodgkin Consortium, EuroNet PHL, Children’s Oncology Group) provided their current definitions for lung involvement, and rationale for staging decisions for the lung cases presented. Based on these discussions, a Delphi survey was drafted containing 12 statements pertaining to the staging criteria for lung lesions and distributed electronically to members of the SEARCH committee representing each consortium. Consensus was defined as a score of 3.75 or greater on a 5-point Likert scale (strongly disagree [1] to strongly agree [5]). Delphi rounds continued until consensus was achieved for all statements, or until a decision was made to remove a statement. Responses were collected anonymously and scores were pooled and reviewed after each round. Extreme scores and all comments were reviewed on committee calls before proceeding to the next round. Results: 21 experts responded to the first Delphi round, including pediatric oncologists, nuclear medicine radiologists, and radiation oncologists. 8 of 12 statements met consensus in Round 1. Several statements were edited to improve clarity and 1 statement was added. A second Delphi round was completed with 20 responses. All statements met consensus with the exception of one which was ultimately removed for group consensus that further investigation was required. Final consensus statements are available in Figure 1. Keywords: Hodgkin lymphoma, non-Hodgkin (pediatric, adolescent, and young adult) No conflicts of interests pertinent to the abstract.