Role of ¹⁸F-FDG-PET/CT in assessment of pediatric Hodgkin’s lymphoma

BACKGROUND: The aim of this study was to assess the prognostic role of interim 18F-FDG-PET/CT in children with pediatric Hodgkin’s lymphoma (PHL). METHODS: We conducted a prospective analysis of 254 Saudi patients with pathologically proven PHL. They underwent interim 18F-FDG-PET/CT after 2 cycles of ABVD with baseline study. Analysis of interim 18F-FDG-PET/CT was done visually according to the Deauville Score (5-point score) as well as a semi-quantitative analysis using maximum standardized uptake value (SUVmax), average SUV (SUVmean2.5 and SUVmean40). The parameters were calculated as absolute values and as percentages of difference between the initial and the interim hottest residual lesion. Follow-up was done for a period of 2.9 years (range, 0.9 to 5.2 years). Clinical outcomes were obtained from medical records. RESULTS: Two hundred and twenty out of 254 children showed PET-ve interim, while 34 were still PET+ve. Univariate analysis showed that the risk stratification, qualitative analysis of interim 18F-FDG-PET/CT were significant predictors for total actuarial survival (TAS) and disease free survival (DFS). Among the semi-quantitative parameters, ∆SUVmean2.5 has the highest hazard ratio. In multivariate analysis, the current study revealed that the three above factors were important prognostic factors that can predict TAS and DFS. However, visual assessment of interim PET canceled the prognostic impact of ∆SUVmean2.5. CONCLUSIONS: Visual assessment of early interim 18F-FDG-PET/CT after 2 cycles of ABVD in PHL showed a very significant role in prediction ofTAS and DFS.