Prognostic value of pretreatment 18F-FDG PET/CT imaging metabolic parameters in patients with early-stage extranodal natural killer/T cell lymphoma / 中华核医学与分子影像杂志

ABSTRACT

Objective@#To investigate the prognostic value of metabolic parameters calculated from pretreatment 18F-fluorodeoxyglucose (FDG) PET/CT images in patients with extranodal natural killer/T cell lymphoma (ENKTL) of stage Ⅰ-Ⅱ.@*Methods@#From August 2010 to April 2018, 67 patients with ENKTL of stage Ⅰ-Ⅱ disease (47 males, 20 females; median age 57 years) in the First Affiliated Hospital of Nanjing Medical University were enrolled, and the clinic data and pretreatment 18F-FDG PET/CT imaging data were retrospectively analyzed. Metabolic tumor volume (MTV) and total lesion glycolysis (TLG) of tumor tissue were calculated from PET/CT images with the threshold value of 40% of maximum standardized uptake value (SUVmax). The optimal cut-off values of progression-free survival (PFS) and overall survival (OS) of SUVmax, MTV and TLG were investigated by using receiver operating characteristic (ROC) curve analysis. Kaplan-Meier method, log-rank test and Cox proportional hazards model were used for data analysis.@*Results@#SUVmax, MTV and TLG of 67 patients were 12.32(8.65, 16.96), 13.13(7.37, 22.74) ml, 92.17(46.54, 198.46), respectively. ROC curve analysis showed that the cut-off values of SUVmax, MTV and TLG were 13.09, 18.05 ml and 152.81, respectively. Univariate analysis showed that B symptoms, lactate dehydrogenase (LDH) level, β2-microglobulin, Eastern Cooperative Oncology Group (ECOG) score, Korean prognostic index (KPI), SUVmax, MTV, TLG and treatment mode (chemotherapy or chemoradiotherapy) were relative factors affecting PFS (χ2 5.466-27.163, all P<0.05). B symptoms, LDH level, β2-microglobulin, EB virus (EBV)-DNA, extra-cavitary extension, ECOG score, KPI, MTV, TLG and treatment mode were relative factors affecting OS (χ2 4.022-34.774, all P<0.05). SUVmax was not the influencing factor of OS(χ2=2.766, P>0.05). Multivariate analysis showed that ECOG score, MTV and TLG were independent prognostic predictors of PFS (relative ratio (RR) 5.107-6.802, all P<0.05), and ECOG score, MTV, TLG and treatment mode were independent prognostic predictors of OS (RR 0.221-9.106, all P<0.05).@*Conclusions@#MTV and TLG from pretreatment 18F-FDG PET/CT images are independent prognostic factors for PFS and OS in patients with ENKTL of stage Ⅰ-Ⅱ. MTV and TLG may be more useful than SUVmax for prognosis.