Brief Article
Copyright ©2012 Baishideng Publishing Group Co., Limited. All rights reserved.
World J Gastroenterol. Jun 21, 2012; 18(23): 2979-2987
Published online Jun 21, 2012. doi: 10.3748/wjg.v18.i23.2979
Diagnostic value for extrahepatic metastases of hepatocellular carcinoma in positron emission tomography/computed tomography scan
Ji Eun Lee, Jae Young Jang, Soung Won Jeong, Sae Hwan Lee, Sang Gyune Kim, Sang-Woo Cha, Young Seok Kim, Young Deok Cho, Hong Soo Kim, Boo Sung Kim, So Young Jin, Deuk Lin Choi
Ji Eun Lee, Jae Young Jang, Soung Won Jeong, Sang-Woo Cha, Young Deok Cho, Institution for Digestive Research, Digestive Disease Center, Department of Internal Medicine, Soonchunhyang University Hospital, Seoul 140-743, South Korea
Sae Hwan Lee, Hong Soo Kim, Institution for Digestive Research, Digestive Disease Center, Department of Internal Medicine, Soonchunhyang University Hospital, Cheon-an 330-721, South Korea
Sang Gyune Kim, Young Seok Kim, Boo Sung Kim, Institution for Digestive Research, Digestive Disease Center, Department of Internal Medicine, Soonchunhyang University Hospital, Bu-cheon 420-767, South Korea
So Young Jin, Department of Pathology, Soonchunhyang University Hospital, Seoul 140-743, South Korea
Deuk Lin Choi, Department of Radiology, Soonchunhyang University Hospital, Seoul 140-743, South Korea
Author contributions: Lee JE, Jang JY, Jeong SW and Choi DL wrote the paper; Lee SH, Kim SG, Cha SW, Kim YS, Cho YD, Kim HS, Kim BS and Jin SY provided clinical advice; Lee JE, Jang JY and Jeong SW performed the research.
Correspondence to: Dr. Jae Young Jang, Institute for Digestive Research, Digestive Disease Center, Department of Internal Medicine, Soonchunhyang University Hospital, 657, Hannam-dong, Yongsan-gu, Seoul 140-743, South Korea. jyjang@schmc.ac.kr
Telephone: +82-2-7099863   Fax: +82-2-7099797
Received: December 9, 2011
Revised: February 6, 2012
Accepted: February 16, 2012
Published online: June 21, 2012
Abstract

AIM: To evaluated the value of 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) scan in diagnosis of hepatocellular carcinoma (HCC) and extrahepatic metastases.

METHODS: A total of 138 patients with HCC who had both conventional imaging modalities and 18F-FDG PET/CT scan done between November 2006 and March 2011 were enrolled. Diagnostic value of each imaging modality for detection of extrahepatic metastases was evaluated. Clinical factors and tumor characteristics including PET imaging were analyzed as indicative factors for metastases by univariate and multivariate methods.

RESULTS: The accuracy of chest CT was significantly superior compared with the accuracy of PET imaging for detecting lung metastases. The detection rate of metastatic pulmonary nodule ≥ 1 cm was 12/13 (92.3%), when < 1 cm was 2/10 (20%) in PET imaging. The accuracy of PET imaging was significantly superior compared with the accuracy of bone scan for detecting bone metastases. In multivariate analysis, increased tumor size (≥ 5 cm) (P = 0.042) and increased average standardized uptake value (SUV) uptake (P = 0.028) were predictive factors for extrahepatic metastases. Isometabolic HCC in PET imaging was inversely correlated in multivariate analysis (P = 0.035). According to the receiver operating characteristic curve, the optimal cutoff of average SUV to predict extrahepatic metastases was 3.4.

CONCLUSION: 18F-FDG PET/CT scan is invaluable for detection of lung metastases larger than 1 cm and bone metastases. Primary HCC having larger than 5 cm and increased average SUV uptake more than 3.4 should be considered for extrahepatic metastases.

Keywords: 18F-fluorodeoxyglucose positron emission tomography/computed tomography scan; Diagnosis; Hepatocellular carcinoma; Extrahepatic metastases