Decrease in total lesion glycolysis and survival after yttrium-90-radioembolization in poorly differentiated hepatocellular carcinoma with portal vein tumour thrombosis

This study aims to evaluate the prognostic role of the decrease in total lesion glycolysis (TLG) assessed by fluorine-18-fluorodeoxyglucose (F-FDG) PET-computed tomography (CT) 1 month after yttrium-90-radioembolization (Y-RE) in patients affected by hepatocellular carcinoma (HCC) with portal vein tumour thrombosis (PVTT). PATIENTS AND METHODS: Twenty-one patients with histologically proven poorly differentiated HCC and evidence of PVTT at the enhanced multislice CT underwent Y-RE. All patients underwent an F-FDG PET-CT scan at baseline and 1 month after the loco-regional therapy. The variation in TLG (ΔTLG) between the two studies was calculated. Patients were divided in two groups (group 1: 1 month ΔTLG >50%, group 2: ΔTLG <50%). Statistical analysis was carried out to assess the prognostic role of TLG in overall survival (OS). RESULTS: On the 21 patients enrolled, all presented a decrease in TLG after the administration of Y-microspheres. The OS was 11.5±1.2 months. Nine out of 21 (42.9%) patients showed ΔTLG more than 50% with a mean OS of 16.8±1.3 months, whereas the remaining 12 (57.1%) patients had ΔTLG less than 50% with a mean OS of 7.5±0.5 months. Statistical analysis showed ΔTLG to be a significant (P<0.001) predictor of survival. None of the other examined variables including age, Child-Pugh classification, previously performed therapies, the presence of extrahepatic metastases, α-fetoprotein and bilirubin levels had a significant prognostic impact on patients' outcome. CONCLUSION: Decrease in TLG measured by F-FDG PET-CT is correlated with a trend towards a longer median survival in patients affected by HCC and PVTT who have undergone Y-RE.