Predictive value of metabolic parameters of baseline 18F-fluorodeoxyglucose positron emission tomography/computed tomography for survival rates of children with lymphoma (a metaanalysis and literature review)

The five-year overall survival (OS) rate for pediatric Hodgkin's (HL) and non-Hodgkin's (NHL) lymphomas remains at 85–95% despite improvements in therapy regimens. The problem of establishing reliable prognostic factors that could help identify high- or ultra-high-risk patients is still unresolved. We performed a systematic literature review and meta-analysis of studies investigating the predictive value of baseline metabolic parameters of ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) in pediatric patients with lymphomas. We systematically searched the following databases: PubMed, Medline, Cochrane Library and Google Scholar. Six retrospective studies (309 patients) evaluating the effect of quantitative parameters derived from baseline PET/CT with ¹⁸F-FDG (maximum standardized uptake value (SUV_max), tumor metabolic volume (MTV), and total lesion glycolysis (TLG)) on OS and event-free survival (EFS) in children with HL and NHL were included in our analysis. We used the Cochrane ROBINS-I tool to assess the quality of studies; the relative risks (RR) for the studied outcomes were calculated with RevMan software, version 5.3. The overall analysis showed that high MTV was associated with a six-fold increase in the relative mortality risk (RR 6.18 (3.15–12.11), p < 0.001) and a more than 5-fold increase in the risk of relapse/progression (RR 5.68 (3.21–10.07), p < 0.001). High values of TLG were associated with an eight-fold increase in the risk of mortality (RR 8.06 (3.35–19.39), p < 0.001) and worse EFS (RR 5.75 (2.99–11.06), p < 0.001). Our results will enable oncologists to expand existing risk assessment systems and improve their predictive effectiveness by using MTV and TLG parameters.