Pretreatment volumetric parameters of FDG-PET predict the survival after Yttrium-90 radio-embolization in metastatic liver disease.

This study aimed to determine the prognostic value of pretreatment FDG-PET in patients with metastatic liver disease undergoing Yttrium 90 (Y) radio-embolization using global disease assessment measures. Data from 16 patients with metastatic liver disease (8 males, 8 females) aged 55-97 years (mean: 67±12) were retrospectively collected. On PET, active malignant lesions in the liver were segmented with an adaptive thresholding system (ROVER software, ABX GmbH, Radeberg, Germany). Conventional measures of PET quantification such as SUVmean, SUVmax, and partial volume-corrected SUVmean (pvcSUVmean) and volumetric parameters including metabolic tumor volume (MTV), total lesion glycolysis (TLG) and pvcTLG were measured. Receiver operating characteristic (ROC) was used to determine the optimal cutoffs for Kaplan-Meier analyses. Kaplan-Meier analysis was performed to estimate progression-free survival (PFS) and overall survival (OS). In addition, Cox regression analysis was used to determine predictors of PFS and OS. There was no correlation between pretreatment conventional parameters of FDG-PET and PFS or OS. In contrast, in the univariate Cox regression analyses, pretreatment volumetric parameters were significant predictors for PFS [TLG (HR: 6.1, =0.02), pvcTLG (HR: 3.9, =0.03) and MTV (HR: 5.8, =0.02)]. Moreover, TLG (HR: 6.1, =0.03), pvcTLG (HR: 5.2, <0.01) and MTV (HR: 10.7, <0.01) were significant prognostic factors for OS. Pretreatment volumetric FDG-PET parameters are prognostic factors for PFS and OS in patients with liver metastasis receiving radio-embolization with Y.