PROGNOSTIC VALUE OF 18F-FDG PET/CT VOLUMETRIC PARAMETERS IN CHILDHOOD, ADOLESCENT, AND YOUNG ADULT HODGKIN LYMPHOMA: A SYSTEMATIC REVIEW FROM THE SEARCH GROUP

Abstract

C. Gowdy, J. Flerlage, J. Seelisch, M. Palese, T. Bradshaw, S. M. Castellino, S. Cho, K. Dieckmann, B. S. Hoppe, S. Howard, K. Kelly, L. Kurch, H. Lai, E. Lopci, J. Lucas, C. Mauz-Körholz, K. McCarten, N. Pandit-Taskar, H. Schöder, J. Steglich, D. Stoevesandt, and S. Voss equally contributing author.

Introduction: In adults with classic Hodgkin lymphoma (cHL), PET volumetric parameters, such as metabolic tumor volume (MTV), are valuable for risk stratification. This study was undertaken to explore the role of metabolic parameters in children, adolescents, and young adults with cHL.

Methods: This systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) method. Five databases were searched on 16th October 2024: MEDLINE (Ovid), EMBASE (Ovid), CINAHL (EBSCO), EBM Reviews (OVID) and the Web of Science Core Collection. Eligible studies were peer-reviewed manuscripts, written in English, published from database inception to the search date that included patients up to 21 years of age with a diagnosis of cHL and a ¹⁸F-FDG PET/CT scan with calculation of MTV. Two authors independently reviewed all studies identified in the literature search.

Results: The search strategy detected 3669 studies from which 1085 duplicates and 2584 studies were excluded following 2-person review of titles and abstracts. Full-text review of 81 papers identified 35 as eligible for inclusion. Fifteen of the papers (43%) evaluated a cohort exclusively < 21 years of age and 20 papers (57%) considered children and adults, with a median of 69 (21–297) participants. All 8 studies that explored the association of baseline MTV and/or TLG (total lesion glycolysis) with known risk factors (ex. bulk, stage, clinical parameters used to define treatment group/level) identified a significant correlation. Twelve papers explored the association of baseline MTV and/or TLG with disease response on PET/CT according to Lugano criteria, of which 9 (75%) demonstrated a statistically significant correlation. Twenty papers explored the association of baseline PET parameters with clinical outcome (ex. overall survival, progression-free survival) and 15 (75%) demonstrated an independent statistically significant correlation. Of 6 studies that explored higher-order radiomic features, 4 (67%) found that they out-performed MTV and/or TLG. Thirty-three of 35 studies detailed the segmentation approach that was used to delineate disease, of which 11 used or recommended an absolute fixed threshold method.

Conclusions: Metabolic PET parameters are valuable for risk stratification; the review has found heterogeneity of results related to differences in patient cohorts, treatment strategies, methods for disease segmentation, and parameter calculation. This group of international experts will provide recommendations regarding the necessary next steps to harmonize the approach and incorporate PET volumetric parameters into clinical practice for children, adolescents and young adults with cHL.

Research funding declaration: none

Keywords: PET-CT; diagnostic and prognostic biomarkers; Hodgkin lymphoma (pediatric, adolescent, and young adult)

No potential sources of conflict of interest.