title: What causes false-negative PET findings for solid-type lung cancer?
abstract: BACKGROUND
  To investigate possible causes for false-negative findings on PET scans for solid-type lung cancers, we retrospectively compared PET findings to clinical and pathological features using multivariate analysis.
  
  
  METHODS
  We reviewed PET/CT records, clinical records, preoperative thin-section CT images, and postoperative pathological records and selected only solid-type primary lung cancers with lesions ≤ 40 mm in diameter that had been definitively diagnosed by surgical resection. PET images with SUVmax of ≥ 2.5 were considered PET-positive. Logistic regression analysis was used to identify independent predictors of PET-positive or negative among five factors: body weight, blood glucose level, lesion size, location, and histological classification.
  
  
  RESULTS
  A total of 187 solid-type primary lung cancers were selected. Forty lesions (21.4%) were judged as PET-negative and 147 lesions (78.6%) were judged as PET-positive. Multivariate logistic analysis for the 187 lesions revealed that lesion size (p<0.001) and histological tumour type (p<0.001) were significant factors for determining whether PET findings were negative.
  
  
  CONCLUSIONS
  Among solid-type lung cancers, lesion size and histopathological findings were significantly associated with FDG uptake. In particular, it warrants attention that lesions ≤ 2 cm and bronchioloalveolar carcinoma and well-differentiated adenocarcinoma have a tendency for negative PET findings.
authors.affiliation: Department of Radiology, Nagoya University Graduate School of Medicine, Japan. iwano45@med.nagoya-u.ac.jp
authors.forename: Shingo
authors.initials: S
authors.lastname: Iwano
authors.forename: Shinji
authors.initials: S
authors.lastname: Ito
authors.forename: Kenichi
authors.initials: K
authors.lastname: Tsuchiya
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Kato
authors.forename: Shinji
authors.initials: S
authors.lastname: Naganawa
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019540:Area Under Curve; D001786:Blood Glucose / Q000378:metabolism; D001835:Body Weight; D005188:False Negative Reactions; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D016015:Logistic Models; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D049268:Positron-Emission Tomography; D012372:ROC Curve; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed
chemical_list: D001786:Blood Glucose; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18