Evaluación del valor pronóstico de los diferentes métodos de cálculo del volumen metabólico tumoral con 18F-FDG PET/TC, en pacientes con linfoma B difuso de células grandes

INTRODUCTION AND OBJECTIVES Metabolic tumor volume (MTV) is a promising indicator of prognosis in diffuse large B-cell lymphoma (DLBCL). The aim of the present study is to evaluate the different methods for the calculation of the basal metabolic tumor volume with 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) in the patients with DLBCL, relating each one of the volumes measured with progression-free survival (PFS) and overall survival (OS). METHODOLOGY This is a retrospective analytical cohort study, in which 34 patients underwent to 18F-FDG PET/CT baseline prior to treatment. We compared three SUV thresholds 2.5, SUV 40% of the maximum SUV and SUV mean hepatic uptake (PERCIST) for the calculation of MTV and total lesion glycolysis (TLG) biomarkers, relating them to the PFS and OS. The best predictive model was selected based on the Akaike's information criterion (AIC) after performing a Cox proportional hazards regression. RESULTS In relation to the PFS, they show statistically significant differences: MTV 2.5, TLG 2.5, MTV 40, TLG 40, MTV and TLG calculated with the PERCIST threshold. Among these, the one that has a lower AIC is MTV 2.5, so it is considered the best parameter to predict the PFS. With respect to OS, it shows statistically significant differences: MTV 2.5, VMT and TLG calculated with the PERCIST threshold. Among these three, the one with the lowest AIC is MTV 2.5, which is why it is considered the best parameter to predict OS. In addition, a higher value of MTV and total tumor glycolysis (TLG), is associated with worse PFS and OS CONCLUSION: The MTV calculated with the threshold SUV 2.5 seems to be the best parameter to predict PFS and OS in patients diagnosed with DLBCL with 18F-FDG PET/CT.