Value of integrated PET/CT in detection of hepatic metastatic deposits

PurposeThe goal of this study was to assess the value of combined PET/CT using 18F-FDG in detection and characterization of hepatic metastatic lesions compared to isolated PET and CT in various malignancies.Patients and methodsThe study included 82 patients divided into six groups of primary malignancies to whom PET/CT scans were done. Detailed retrograde lesion based and patient based analyses were performed for 441 detected hepatic lesions in 82 patients to detect metastasis on PET, CT and PET/CT. A final diagnosis of metastasis was confirmed by biopsy or by further clinical and radiologic work-up.ResultsRegarding lesion based analysis, the PET/CT showed 98% sensitivity, 100% specificity, 100% PPV, 84% NPV and 98% accuracy compared with 98%, 98%, 99.7%, 84% and 98%, respectively, for PET, and 95%, 81%, 98%, 63% and 94%, respectively, for CT. In patient-based analysis, PET/CT and PET showed 99% sensitivity, 100% specificity, 100% PPV, 90% NPV and 99% accuracy compared with 100%, 56%, 95%, 100% and 95%, respectively for CT. The combined PET/CT has significantly improved the low CT sensitivity as well as both CT and PET specificities.ConclusionPET/CT provides accurate detection of hepatic metastasis and their metabolic nature which significantly affect further management.