title: FLT PET/CT Is Better Than FDG PET/CT in Differentiating Benign From Malignant Pancreatobiliary Lesions.
abstract: OBJECTIVE
  F-fluorothymidine (FLT), unlike FDG, is incorporated exclusively into DNA and is considered a specific marker of cell proliferation. The role of FLT PET/CT scan in differentiating benign from malignant pancreatobiliary tumors is unknown.
  
  
  METHODS
  Twenty-five suspected pancreatobiliary tumors on contrast-enhanced CT (CECT) scan in 23 patients were evaluated by FDG PET/CT and FLT PET/CT scans. The histopathology or fine-needle aspiration cytology was considered as criterion standard for the diagnosis. Surgeons were blinded to FLT PET/CT results. Management decision was guided by clinical and CECT scan and FDG PET/CT.
  
  
  RESULTS
  Five of 23 patients had metastatic disease on CECT imaging. The remaining 18 underwent exploratory laparotomy. Two of them had synchronous lesions. Histopathology/fine-needle aspiration cytology confirmed malignancy in 17 lesions and benign disease in the remaining 8 lesions. All 8 benign lesions were negative on FLT PET/CT. Seven of the 8 benign lesions were clinically diagnosed as malignancy on CECT and FDG PET/CT. The specificity, positive predictive value, and accuracy were higher for FLT PET/CT (100%, 100%, and 92%) compared with CECT (12.5%, 70.83%, and 72%) and FDG PET/CT (12.50%, 69.57%, and 68%). However, the sensitivity of FLT PET/CT (88.24%) was similar to CECT (100%) and FDG PET/CT (94.12%).
  
  
  CONCLUSIONS
  Molecular-based FLT PET/CT is a better imaging than FDG PET/CT in differentiating benign from malignant lesions in the pancreatobiliary region. It has a potential to bring down the incidence of preventable radical resection in suspected pancreatobiliary tumors.
authors.affiliation: From the Departments of *General Surgery, †Nuclear Medicine, ‡Gastroenterology, and §Hepatology, Post Graduate Institute of Medical Education and Research, Chandigarh, India.
authors.forename: P M
authors.initials: PM
authors.lastname: Vineeth Kumar
authors.forename: G R
authors.initials: GR
authors.lastname: Verma
authors.forename: B R
authors.initials: BR
authors.lastname: Mittal
authors.forename: Kanhaiyalal
authors.initials: K
authors.lastname: Agrawal
authors.forename: Rahul
authors.initials: R
authors.lastname: Gupta
authors.forename: Rakesh
authors.initials: R
authors.lastname: Kochhar
authors.forename: Virendra
authors.initials: V
authors.lastname: Singh
authors.forename: Lileshwar
authors.initials: L
authors.lastname: Kaman
authors.forename: Rajinder
authors.initials: R
authors.lastname: Singh
mesh_terms: D000328:Adult; D000368:Aged; D001661:Biliary Tract Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D044963:Biopsy, Fine-Needle; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D010190:Pancreatic Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18