SUVmax values in FDG-PET/CT scans of patients with HCC: A possible new prognostic factor

Objectives HCC is the most frequent liver cancer. Hepatitis B and C are risk factors. Alpha-fetoprotein (AFT) is used as a tumor marker. Prognosis is very poor, and mainly based on: tumor size and TNM staging. Management is controversial. Different management-trees and treatment options based on prognostic factors exist. Aggressive surgery or liver transplant in early disease confined to the liver is probably the only cure. Metastasis is considered bad prognoses and tends to be managed with just supportive care. It has been postulated that additional prognostic factors could improve the management of these patients. The goal of this study was to assess if SUVmax values in FDG-PET/CT scans performed in patients with HCC at diagnoses could be used as a new prognostic factor.

Methods 33 patients (30♂, 3♀), age 64.5±8.8 yo, with hepatitis B and/or C, elevated AFP (range 50,078-2.5) and newly diagnosed HCC were imaged with contrast-enhanced CT and FDG-PET/CT. SUVmax of the primary tumors was calculated in all cases. SUVmax values were correlated to bad prognoses based on incidence of metastatic disease.

Results SUVmax levels ranged from 2.1-39.9 (mean 7.0±6.77). All patients with SUVmax>6 showed metastases (8/30) at the time of diagnoses, with exception of three patients. Using a cutoff value of SUVmax=6, 72.7% of patients with SUVmax>6 showed metastases and 88% of patients without metastases had SUVmax<6. A Spearman Rank Correlation between metastases and SUVmax values showed a rho=0.6988 and a significant two-sided p-value < 0.04. AFP and tumor size were not significant.

Conclusions SUVmax levels in FDG-PET/CT scans performed in patients with HCC tumors at time of diagnoses could become a new prognostic factor, since in our group of patients higher SUVmax levels seem to significantly correlate with higher incidence of metastatic disease at the time of diagnoses. SUVmax as a new prognostic factor could eventually improve the management of these patients in the near future