Detection of Klatskin's tumor in extrahepatic bile duct strictures using delayed 18F-FDG PET/CT: preliminary results for 22 patient studies.
Detection of cholangiocarcinoma in extrahepatic bile duct strictures is a continuing challenge in clinical practice because brush cytology taken at endoscopic retrograde cholangiography has an average sensitivity of 50%. The aim of this study was to evaluate the effectiveness of dual-modality PET/CT using (18)F-FDG for noninvasive differentiation of extrahepatic bile duct strictures.


METHODS
Twenty-two PET/CT studies were performed on 20 patients (10 women, 10 men; mean age +/- SD, 63 +/- 14 y) with extrahepatic bile duct strictures on endoscopic retrograde cholangiography. PET imaging was started 101 +/- 22 min after injection of 369 +/- 48 MBq of 18F-FDG. Blood glucose was 100 +/- 20 mg/dL. PET images were reconstructed iteratively with attenuation correction based on a rescaling of the CT image. CT was performed within 1 min before the PET study, with the patient in the same position. CT was used to place a volume of interest 5 cm in diameter at the liver hilus for quantitative evaluation of PET images by means of standardized uptake values (SUVs).


RESULTS
Final diagnosis was histologically proven cholangiocarcinoma in 14 cases and benign causes of strictures in 8 cases without evidence of malignancy during a follow-up of 18 +/- 3 mo. All patients with cholangiocarcinoma presented with focal increased uptake in the liver hilus with an SUV of 6.8 +/- 3.3 (range, 3.9-15.8), compared with 2.9 +/- 0.3 (range, 2.5-3.3) in patients with benign causes of strictures (P = 0.003). There was a clear cutoff SUV of 3.6 for detection of malignancy in the liver hilus.


CONCLUSIONS
18F-FDG PET/CT provided high accuracy for noninvasive detection of perihilar cholangiocarcinoma in extrahepatic bile duct strictures.
Department of Nuclear Medicine, University Hospital Bonn, Bonn, Germany. michael.reinhardt@ukb.uni-bonn.de
Michael J
MJ
Reinhardt
Holger
H
Strunk
Thomas
T
Gerhardt
Roland
R
Roedel
Ursula
U
Jaeger
Jan
J
Bucerius
Tilman
T
Sauerbruch
Hans-Juergen
HJ
Biersack
Franz L
FL
Dumoulin
D000328:Adult; D000368:Aged; D001650:Bile Duct Neoplasms / Q000175:diagnosis*; D005260:Female; D019788:Fluorodeoxyglucose F18; D006500:Hepatic Duct, Common / Q000000981:diagnostic imaging*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D018285:Klatskin Tumor / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography / Q000379:methods*; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013382:Subtraction Technique; D014057:Tomography, X-Ray Computed / Q000379:methods*
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18