Purpose: The aim of this study was to explore the prognostic value of total metabolic tumor volume (TMTV) at baseline 18F-FDG PET/CT in patients diagnosed with peripheral T-cell lymphoma (PTCL).
Materials and methods: Eighty-four newly diagnosed PTCL patients who underwent baseline 18F-FDG PET/CT prior to treatment between March 2009 and January 2019 were enrolled in this retrospective study. The FDG-avid lesions in each patient were segmented using semiautomated software to calculate the maximum standardized uptake value (SUVmax), total metabolic tumor volume (TMTV), and total lesion glycolysis (TLG) values using the boundaries of voxels presenting with the 41% SUVmax threshold method. Progression-free survival (PFS) and overall survival (OS) were used as end points to evaluate patient prognosis. The log-rank test and Cox regression analyses were used to evaluate PFS and OS.
Results: ROC curve analysis indicated an ideal TMTV cut-off value of 228.8 cm3. During the 4-131 months (29.2 ± 28.5 months) follow-up period, high TMTV was significantly associated with worse PFS and OS. TMTV and the international peripheral T-cell lymphoma project score (IPTCLP) were independent predictors of PFS and OS with multivariate analysis. The combination of TMTV and the IPTCLP may provide significantly better risk substratification in PFS and OS of PTCL patients.
Conclusions: Both TMTV and IPTCLP are independent predictors of PTCL patient survival outcomes. Moreover, the combination of TMTV and IPTCLP improved patient risk stratification and may contribute to personalized therapeutic regimens.
Keywords: PET/CT; Peripheral T-cell lymphoma; Prognosis; Total metabolic tumor volume.