MR imaging versus PET/CT for evaluation of pancreatic lesions.
OBJECTIVE
To retrospectively determine the diagnostic accuracy of magnetic resonance imaging (MRI) and combined positron emission tomography/computed tomography (PET/CT) in the differential diagnosis of benign and malignant pancreatic lesions.


METHODS
Twenty-seven patients (15 women/12 men, mean age 56.5 years) with MR imaging and PET/CT studies performed to differentiate benign and malignant pancreatic lesions were identified between October 2008 and October 2010. Both MR and PET/CT data sets were retrospectively and blindly evaluated by two independent readers (4 readers total) with different degrees of experience, using a visual five-point score system. The results were correlated with final diagnosis obtained by histopathology.


RESULTS
17 patients had malignant diseases and 10 patients had benign diseases. Depending on the observer, the sensitivity, specificity, positive predictive value and negative predictive value of MRI varied between 88-94%, 50-80%, 75-89% and 71-89% respectively. Sensitivities, specificities, positive predictive values and negative predictive values of PET/CT were 73%, 56%, 73% and 56% respectively. The diagnostic accuracy of MR for the differential diagnosis of pancreatic lesions was 74-89%, compared with 67% for PET/CT. The weighted Cohen's kappa coefficient was 0.47 at MR and 0.53 at PET/CT.


CONCLUSIONS
MRI achieved higher sensitivity and specificity in the differential diagnosis of pancreatic lesions.
Department of Radiology Hospital S. Francisco Xavier, Estrada do Forte do Alto do Duque, 1495-005 Lisbon, Portugal. sara.beliao@clix.pt
Sara
S
Belião
Alexandra
A
Ferreira
Irina
I
Vierasu
Didier
D
Blocklet
Serge
S
Goldman
Thierry
T
Metens
Celso
C
Matos
D000368:Aged; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D064847:Multimodal Imaging / Q000379:methods*; D015588:Observer Variation; D010190:Pancreatic Neoplasms / Q000175:diagnosis*; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18