Prognostic significance of ¹⁸F-FDG uptake in hepatocellular carcinoma treated with transarterial chemoembolization or concurrent chemoradiotherapy: A multicenter retrospective cohort study

This study aimed to assess the prognostic value of ¹⁸F-FDG uptake in hepatocellular carcinoma (HCC) patients who had transarterial chemoembolization (TACE) or concurrent intraarterial chemotherapy with external-beam radiotherapy (CCRT) and to compare the prognosis between patients treated with TACE and those with CCRT according to ¹⁸F-FDG uptake. Methods: Two hundred fourteen intermediate- to-advanced-stage HCC patients without extrahepatic metastasis who underwent staging ¹⁸F-FDG PET/CT before TACE (153 patients) or CCRT (61 patients) were recruited from 7 hospitals. Progressionfree survival (PFS) and overall survival (OS) were compared using an optimal cutoff value for tumor-to-normal liver uptake ratio (TLR). Further, PFS and OS were compared according to treatment modalities (TACE vs. CCRT) using the same TLR cutoff value. Results: On multivariate analysis, age and TLR were independent prognostic factors for PFS (P < 0.050). For OS, Child-Pugh classification and TLR were independent prognostic factors (P < 0.050). When the TLR was greater than 2.0, patients treated with CCRT showed significantly better PFS and OS than those treated with TACE after adjusting for tumor size and number (P = 0.014, for all). In contrast, there was no significant difference in PFS and OS between patients treated with TACE or CCRT when the TLR was 2.0 or less. Conclusion: ¹⁸F-FDG uptake was an independent prognostic factor for PFS and OS in HCC patients treated with TACE or CCRT. Especially, in HCCs with high ¹⁸F-FDG uptake, patients treated with CCRT showed better survival than those treated with TACE. ¹⁸F-FDG PET/CT may help determine the treatment modality for intermediate-to-advanced-stage HCCs.