RT Journal Article
SR Electronic
T1 11C-Acetate and 18F-FDG PET/CT characteristics for a cohort of asymptomatic patients with non-specific CT/MR findings subsequently diagnosed of intrahepatic cholangiocarinoma
JF Journal of Nuclear Medicine
JO J Nucl Med
FD Society of Nuclear Medicine
SP 318
OP 318
VO 52
IS supplement 1
A1 Ho, Chi-Lai
A1 Chen, Sirong
A1 Leung, Yim Lung
A1 Cheng, Thomas
A1 Wong, Kwong Kuen
YR 2011
UL http://jnm.snmjournals.org/content/52/supplement_1/318.abstract
AB 318 Objectives Cholangiocarcinoma (CCC) is often in an advanced stage by the time symptoms develop and the prognosis is poor. We aim to evaluate the dual-tracer (11C-acetate: ACT; 18F-FDG: FDG) PET/CT characteristics for a small cohort of asymptomatic patients with non-specific CT/MR findings subsequently diagnosed of intrahepatic CCC. Methods 8 (F: 5, M: 3; mean age: 57±14y) consecutive patients in year 2009~10 were referred for PET/CT because of liver lesions with atypical contrast-enhancing characteristics in 3-phase CT or atypical signal/contrast changes in MR without signs of biliary ductal dilatation/obstruction. By CT/MR interpretation, they were considered indeterminate in regard to benign vs. malignant or primary vs. secondary neoplasm of liver. All patients had dual-tracer PET/CT before they were confirmed of CCC (peripheral: 7, hilar: 1) by histopathology. The lesion-to-liver SUV ratio (LSR) for the largest lesion was measured in each patient. Results All patients had normal serum CEA concentration and 2 had elevated AFP level (24.4 and 22.7ug/l). Dual-tracer PET/CT showed no extrahepatic primary cancer in all patients. In 7/8 patients correctly diagnosed as CCC, the liver lesions were markedly hypermetabolic for FDG (LSR range: 3.0~5.4, mean LSR=4.1±0.9) but hypo/iso- metabolic (hypo: 6, iso: 1) for ACT including 2 misdiagnosed as bile duct adenoma by ERCP biopsy before PET/CT. One patient (HBV+, AFP-) showed negative uptake on both ACT and FDG PET/CT. Dual-tracer PET/CT showed absence of nodal, vascular or distant metastases in 7 patients, who were then treated by complete surgical resection. One patient was found of vascular and nodal metastases and was treated by chemotherapy. All patients were currently alive (follow-up period: 6 mo~1.5y, median, 1y). Conclusions Dual-tracer PET/CT characteristics of highly intense FDG and negative ACT uptake may have incremental value for the diagnosis of intrahepatic CCC in patients with no localizing symptoms and indeterminate CT/MR findings