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

Abstract

Purpose: The 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 methods: The 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. Results: Regarding 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. Conclusion: PET/CT provides accurate detection of hepatic metastasis and their metabolic nature which significantly affect further management.

Keywords

• CT
• PET
• PET/CT
• Hepatic metastasis