The prognostic value of the metabolic tumor volume calculated from baseline 18FDG PET/CT in patients with newly diagnosed diffuse large B-cell lymphoma
Background: study of the prognostic role of quantitative indicators for assessing the metabolic activity of the process in patients with newly diagnosed in patient with diffuse large B-cell lymphoma (DLBCL). Patients and methods: metabolic bulk volume (MBV), defined as the metabolic volume of the largest lesion, was retrospectively investigated in 47 patients with DLBCL who underwent baseline pre-treatment 18FDG PET-CT at N.N. Alexandrov National Cancer Center of Belarus. Results: semi-automatically segmented (41% SUVmax) total metabolic tumor volume (TMTV) and MBV underwent receiver operating characteristic analysis, identifying optimal thresholds of 600 cm3 for the TmTv and 275 cm3 for the MBV. According to Cox monovariate analysis, the International prognostic index (IPI) and MBV were predictors for progression-free survival (PFS) (HR 2.9 and 2.8, respectively). At multivariate analysis only IPI was independent predictors for PFS (HR 2.7). In subgroup with low IPI (0-2) higher MBV level was strongly associated with worse prognosis: a 3-year PFS rates in patients with MBV>275 cm3 and 3 were 53,8% and 89,5%, respectively (p=0.01). Conclusion: the baseline MBV can be an efficient tool for the risk stratification of aggressive lymphoma.