18F-FDG PET/CT in diagnosis of malignant pericardial lesions

Objective To assess the value of integrated 18 F-fluorodeoxyglucose (FDG) PET/CT in differentiation of malignant and benign pericardial effusion. Methods 18F-FDG PET/CT were performed in 23 patients with pericardial effusion. The detected soft tissue tumor or nodulous lession in pericardium or the thickened pericardium, with the maximum standardized uptake value( SUVmax ) ≥2.5, was defined as PET/CT-positive. The invaded lession in pericardium with SUVmax ≥2.5 was also as the positive. The difference of SUVmax of benign and malignant lesions was analyzed with two-independent-sample test of nonparametric tests. The final diagnosis was confirmed by biopsy or post-operative pathology. Results The diagnosis were confirmed with 14 malignant and 9 benign lesions. The median of SUVmax was 6.0 in malignancy group and 2.2 in benign group (z= -3. 279, P =0.001 ). According to the pathology results, there were one false negative case and two false positive cases with PET/CT imaging interpretation. The sensitivity, specificity,accuracy, positive predictive value ( PPV ) and negative predictive value ( NPV ) of 18 F-FDG PET/CT in diagnosis of benignity or malignance of pericardium effusion were 92.9% ( 13/14), 7/9, 87.0% (20/23),86.7% (13/15) and 7/8, respectively. Conclusion For the patients with pericardium effusion 18F-FDG PET/CT may be a helpful modality for malignancy differentiation Key words: Pericardial effusion;  Neoplasms;  Tomography, emission-computed; Tomography, X-ray computed;  Deoxygluxose