FLT-PET CT Scan can avoid radical surgery in masquerading pancreatobiliary lesions

Abstract

Background: The purpose of this study was to evaluate the efficacy of this marker (FLT-PET CT scan) and to compare it with FDG-PET scan in differentiating benign from malignant diseases in suspected bilio-pancreatic tumors. Methodology: It is a prospective observational study from July 2013 to April 2017. Suspected Pancreaticobiliary malignancies were included. FDG-PET/CT and FLT-PET/CT was done. Histopathology of the resected specimen or FNAC was considered the gold standard for diagnosis. Results: Fifty-six patients harboring 58 suspected lesions of pancreatobiliary malignancy were included in this study Two patients had synchronous lesions in gall bladder and pancreas. Majority of patients(75.8%,44/58) had gall bladder carcinoma. Thirty-five patients underwent laparotomy, thirty of them were resorted to radical surgery. Eighteen lesions(31%) were confirmed as benign(XGC+Chr. Cholecystitis=14, Ch.Pancreatitis+Pancreatic lipodystrophy=4) on histological examination. The result of FLT-PET were better than FDG-PET. The sensitivity, specificity, PPV and NPV & accuracy of FLT-PET was 92.5%, 100%, 100%, 84.2% and 94.6% respectively. The sensitivity, specificity, PPV and NPV & accuracy of FDG-PET was 97.5%, 31.2%, 78%, 83.3% and 78.5% respectively. Adding CA19-9 for detecting malignancy accuracy increases to 98.2%. On analyzing with ROC, at SUVmax = 2 on FLT-PET, the sensitivity and specificity for detecting malignancy in all pancreaticobiliary lesions was 92.5% and 100% respectively(AUC = 0.91). AUC for FDG-PET CT in pancreaticobiliary lesions was 0.624. Conclusion: FLT-PET is better than FDG-PET scan in differentiating benign pancreaticobiliary lesions. By employing FLT-PET CT as the diagnostic tool, it is predicted that 43.3% of radical surgery done for benign bilio-pancreatic lesions can be avoided.