Aim: To investigate the correlation of ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography (PET) with clinical features and the prediction of treatment response.
Methods: A total of 83 hepatocellular carcinoma (HCC) patients undergoing ¹⁸F-FDG PET before transarterial chemolipiodolization with systemic chemo-infusion between October, 2006 and May, 2009 were retrospectively enrolled. The patients included 68 men and 15 women (mean age, 60 ± 10.7 years). The effect of (18)F-FDG-monitored PET uptake on clinical features and on the evaluated treatment response was ascertained with modified Response Evaluation Criteria in Solid Tumors. The PET parameters of maximal standardized uptake value of the tumor (Tsuv(max)), the ratio of the tumor maximal standardized uptake value (SUV) to the liver maximal SUV (Tsuv(max)/Lsuv(max)) and the ratio of tumor maximal SUV to the liver mean SUV (Tsuv(max)/Lsuv(mean)) were tested as predictive factors.
Results: Among the 3 SUV parameters, the Tsuv(max)/Lsuv(mean) ratio (cutoff value of 1.90) was significantly associated with tumor burden including tumor size, tumor number, α-fetoprotein levels and tumor stage (P < 0.001, P = 0.008, P = 0.011, P < 0.001, respectively). The objective response rates in patients with a high SUV ratio (≥ 1.90) were significantly better than those with a low SUV ratio (< 1.90) (P = 0.020). The overall survival rates of patients exhibiting a low Tsuv(max)/Lsuv(mean) ratio (< 1.90) and those with a high SUV ratio (≥ 1.90) was 38.2 and 10.3 mo, respectively (P < 0.01). However, the time to progression showed no significant difference between the groups (P = 0.15).
Conclusion: ¹⁸F-FDG PET can be an important predictor of HCC treatment. In particular, the Tsuv(max)/Lsuv(mean) ratio (cutoff value of 1.90) can provide useful information in treatment prognosis for HCC patients treated with locoregional therapy.
Keywords: 18F-fluorodeoxyglucose positron emission tomography; Overall survival; Predictive factor; Transarterial chemolipiodolization with systemic chemo-infusion; Treatment response.