title: Diagnostic performance of 18F-FDG PET/contrast-enhanced CT versus contrast-enhanced CT alone for post-treatment detection of ovarian malignancy.
abstract: OBJECTIVE
  The aim of this study was to evaluate the diagnostic performance of combined fluorine-18 fluorodeoxyglucose (F-FDG) PET/contrast-enhanced computed tomography (Ce-CT) in comparison with Ce-CT alone for the detection of residual/recurrent tumor after initial treatment of malignant ovarian tumors.
  
  
  METHODS
  The study prospectively recruited 111 patients with a clinical suspicion of ovarian tumor recurrence. Each patient underwent F-FDG PET/computed tomography (CT) with low-dose CT, followed immediately by Ce-CT. Study-based analyses for a total of 136 scans were carried out. For each study, 11 subsites were assessed on a four-point score (score 0=definitely benign, score 1=probably benign, score 2=probably malignant, and score 3=definitely malignant). The subsites were collectively categorized into four groups: local tumor site, peritoneum, pelvi-abdominal lymph nodes, and other sites (e.g. liver, lung, bone, brain, etc). The final diagnosis of disease status was made on subsequent follow-up by conventional imaging (CT/MRI), F-FDG PET/CT, or histopathology whenever possible.
  
  
  RESULTS
  Of the 136 studies evaluated, 97 (71%) studies had recurrent/residual disease and 39 (29%) studies were disease free on the basis of the final diagnosis. F-FDG PET/Ce-CT and Ce-CT had a sensitivity, specificity, negative predictive value, positive predictive value, and accuracy of 96 versus 84%, 92 versus 59%, 90 versus 59%, 97 versus 84%, and 95 versus 76%, respectively. F-FDG PET/Ce-CT was significantly more sensitive, specific, and accurate compared with Ce-CT, with P-values of 0.002, 0.001, and less than 0.0001, respectively. Site-based analyses also showed significant differences.
  
  
  CONCLUSIONS
  CombinedF-FDG PET/Ce-CT significantly outperforms Ce-CT alone in the post-treatment detection of malignant ovarian tumors.
authors.affiliation: aClinical Oncology and Nuclear Medicine Departments of bRadiology cOncology, Faculty of Medicine, Cairo University, Cairo dNuclear Medicine Unit, South Egypt Cancer Institute, Assiut University, Assiut, Egypt.
authors.forename: Ahmed
authors.initials: A
authors.lastname: Tawakol
authors.forename: Yasser G
authors.initials: YG
authors.lastname: Abdelhafez
authors.forename: Amr
authors.initials: A
authors.lastname: Osama
authors.forename: Emad
authors.initials: E
authors.lastname: Hamada
authors.forename: Sherif
authors.initials: S
authors.lastname: El Refaei
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D003287:Contrast Media; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008207:Lymphatic Metastasis / Q000000981:diagnostic imaging; D008875:Middle Aged; D018365:Neoplasm, Residual / Q000000981:diagnostic imaging / Q000473:pathology / Q000628:therapy; D010051:Ovarian Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology / Q000628:therapy*; D000072078:Positron Emission Tomography Computed Tomography; D012008:Recurrence; D051598:Whole Body Imaging; D055815:Young Adult
chemical_list: D003287:Contrast Media; D019788:Fluorodeoxyglucose F18