Abstract: Objective To explore the clinical value of ¹⁸F-FDG PET/CT scan in patients with hepatocellular carcinoma （HCC） and hepatic microvascular invasion （MVI）. Methods We retrospectively analyzed the clinical materials of 99 patients with HCC who admitted to our hospital between February 2014 and December 2015. All these 99 patients received ¹⁸F-FDG PET/CT scan and hepatectomy thereafter,and the postoperative histopathological examination was done to confirm the existence of MVI. Results Out of the 99 patients with HCC,the postoperative pathological examination showed the existence of MVI in 42,and without MVI in 57 cases;the ¹⁸F-FDG PET/CT scan showed that the intrahepatic tumor irregular and mostly rounded,some accompanied by subfoci,presenting with low density or slightly low density shadows. The PET/CT examination was positive in 73（73.7%） cases,85.7% in patients with MVI,and 64.9% in patients without MVI（P<0.05）;the tumor diameter in patients with MVI positive was （7.6±2.8） cm,significantly larger than（5.4±2.4） cm in patients without MVI,and the tumor maximum standardized uptake value （SUVmax） was （7.4±5.2）,significantly higher than 【（5.3±5.2）,P<0.05】 in patients with MVI negative;the histological types of hepatocellular carcinoma in patients with and without MVI were not significantly different （P>0.05）,while the percentage of tumor differentiation type III/IV was much higher in patients with MVI as compared to that in patients without （88.1% vs. 75.4%,P<0.05）;all the patients were followed-up for 12 to 24 months with the median of 18 months,the one-year total survival was 81.8% and the disease-free survival rate was 60.6%;further analysis showed that the one-year survival and one-year disease-free survival rate in patients with MVI positive were 66.7% and 47.6%,significantly lower than 91.2% and 70.2%,respectively （P<0.05） in patients with MVI negative. Conclusion s The patients with hepatocellular carcinoma and hepatic microvascular invasion have some characteristics when the ¹⁸F-FDG PET/CT scan is done,which should be summarized and its implications needs further investigation.

Key words: Hepatocellular carcinoma, ¹⁸F-FDG PET/CT scan, Microvascular invasion, Survival