Highly metabolic thrombus of the portal vein: 18F fluorodeoxyglucose positron emission tomography/computer tomography demonstration and clinical significance in hepatocellular carcinoma.
OBJECTIVE
To assess the ability of (18)F-fluorodeoxyglucose positron emission tomography/computer tomography ((18)F-FDG PET/CT) to differentiate between benign and malignant portal vein thrombosis in hepatocellular carcinoma (HCC) patients.


METHODS
Five consecutive patients who had HBV cirrhosis, biopsy-proven HCC, and thrombosis of the main portal vein and/or left/right portal vein on ultrasound (US), computer tomography (CT) or magnetic resonance imaging (MRI) were studied with (18)F-FDG PET/CT. The presence or absence of a highly metabolic thrombus on (18)F-FDG PET/CT was considered diagnostic for malignant or benign portal vein thrombosis, respectively. All patients were followed-up monthly with US, CT or MRI. Shrinkage of the thrombus or recanalization of the vessels on US, CT or MRI during follow-up was considered to be definitive evidence of the benign nature of the thrombosis, whereas enlargement of the thrombus, disruption of the vessel wall, and parenchymal infiltration over follow-up were considered to be consistent with malignancy. (18)F-FDG PET/CT, and US, CT or MRI results were compared.


RESULTS
Follow-up (1 to 10 mo) showed signs of malignant thrombosis in 4 of the 5 patients. US, CT or MRI produced a true-positive result for malignancy in 4 of the patients, and a false-positive result in 1. (18)F-FDG PET/CT showed a highly metabolic thrombus in 4 of the 5 patients. (18)F-FDG PET/CT achieved a true-positive result in all 4 of these patients, and a true-negative result in the other patient. No false-positive result was observed using (18)F-FDG PET/CT.


CONCLUSIONS
(18)F-FDG PET/CT may be helpful in discriminating between benign and malignant portal vein thrombi. Patients may benefit from (18)F-FDG PET/CT when portal vein thrombi can not be diagnosed exactly by US, CT or MRI.
Sun
Long
L
Minnan PET Center, The First Hospital of Xiamen, Fujian Medical University, Xiamen 316003, Fujian Province, China.
Guan
Yong-Song
YS
Pan
Wei-Ming
WM
Chen
Gui-Bing
GB
Luo
Zuo-Ming
ZM
Wei
Ji-Hong
JH
Wu
Hua
H
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D006528:Carcinoma, Hepatocellular / Q000175:diagnosis* / Q000628:therapy*; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000494:pharmacology*; D006801:Humans; D008113:Liver Neoplasms / Q000175:diagnosis* / Q000628:therapy*; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D011169:Portal Vein / Q000473:pathology*; D049268:Positron-Emission Tomography / Q000379:methods*; D013927:Thrombosis / Q000473:pathology*; D014057:Tomography, X-Ray Computed / Q000379:methods*
D019788:Fluorodeoxyglucose F18