title: Ability of 18-fludeoxyglucose positron emission tomography/CT to detect incidental cancer.
abstract: OBJECTIVE
  To determine the prevalence and clinical features of pathologically proven incidental cancer (IC) detected by whole-body fluorine-18 fludeoxyglucose ((18)F-FDG) positron emission tomography (PET)/CT, as well as the incidence of false-positive and false-negative results.
  
  
  METHODS
  We retrospectively reviewed reports derived from (18)F-FDG PET/CT images of 3079 consecutive patients with known or suspected malignancies for 3 years. Discrete focal uptake indicating IC was identified from reports as well as pathological or clinical diagnoses, and the clinical courses were investigated. The false-positive result was defined as uptake indicating IC but not pathologically confirmed as malignant during follow-up. The false-negative result was defined as pathologically proven IC detected by another modality at initial clinical work-up or diagnosed during the follow-up period.
  
  
  RESULTS
  We found (18)F-FDG uptake indicating IC in 6.7% of all patients, and IC was pathologically proven in 2.2% of all patients. The most common sites were the colon, lung and stomach. The median survival duration of patients with IC was 42 months. The results were false positive in 4.5% of all patients, and the results were false negative in 2.3% of all patients.
  
  
  CONCLUSIONS
  (18)F-FDG PET/CT is a valuable tool for detecting IC. The rates of false-positive and false-negative results are within acceptable range.
  
  
  CONCLUSIONS
  This is the first report to describe the survival of patients with IC, and the detailed features of false-negative results at actual clinical settings.
authors.affiliation: 1 Department of Radiology, Ogaki Municipal Hospital, Ogaki, Gifu, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Sone
authors.forename: A
authors.initials: A
authors.lastname: Sobajima
authors.forename: T
authors.initials: T
authors.lastname: Kawachi
authors.forename: S
authors.initials: S
authors.lastname: Kohara
authors.forename: K
authors.initials: K
authors.lastname: Kato
authors.forename: S
authors.initials: S
authors.lastname: Naganawa
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015179:Colorectal Neoplasms / Q000000981:diagnostic imaging*; D003951:Diagnostic Errors; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D033162:Incidental Findings; D008175:Lung Neoplasms / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D049268:Positron-Emission Tomography / Q000379:methods*; D019275:Radiopharmaceuticals; D012189:Retrospective Studies
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18