title: Impact of 18F-FDG-PET/CT on treatment strategy in colorectal cancer lung metastasis before lung radiofrequency ablation.
abstract: OBJECTIVE
  The aim of the study was to evaluate prospectively the clinical impact of 2-(F)-fluoro-2-deoxy-D-glucose (F-FDG) PET/computed tomography (CT) on the pretreatment assessment of patients with colorectal lung metastasis before radiofrequency (RF) ablation.
  
  
  METHODS
  The institutional review board approved this prospective study. The eligibility criteria for lung RF ablation were the presence of five or fewer colorectal lung metastases with a maximum tumor size of 3 cm and absence of extrapulmonary lesions. Lung RF ablation candidates who underwent pretreatment PET/CT studies were included. The incidence of detection of unexpected recurrent lesions on PET/CT was evaluated, along with its impact on subsequent treatments. Factors linked with the incidence of unexpected recurrent lesions were evaluated using univariate and multivariate analyses.
  
  
  RESULTS
  Between October 2008 and June 2011, 60 patients were enrolled. Among the unexpected abnormal F-FDG accumulations found in 13 patients (21.7%), presence of extrapulmonary lesions was proved in 12 patients (20.0%, 12/60), prompting treatment strategy changes. One false-positive case was found (1.7%, 1/60). The sensitivity, specificity, and accuracy in detecting unexpected lesions by PET/CT were, respectively, 100, 97.9, and 98.3%. Elevation of the serum carcinoembryonic antigen level (>6.0 ng/ml) was the only significant factor linked with unexpected lesions in both univariate (P=0.02) and multivariate analyses (P=0.02).
  
  
  CONCLUSIONS
  A PET/CT study should be performed in patients with colorectal lung metastasis before selecting them for lung RF ablation, especially when the carcinoembryonic antigen level is elevated.
authors: Department of Radiology, Mie University School of Medicine, Tsu, Japan. h-kodama@clin.medic.mie-u.ac.jp
authors: Hiroshi
authors: H
authors: Kodama
authors: Koichiro
authors: K
authors: Yamakado
authors: Haruyuki
authors: H
authors: Takaki
authors: Naohisa
authors: N
authors: Suzawa
authors: Tomomi
authors: T
authors: Yamada
authors: Kan
authors: K
authors: Takeda
mesh_terms: D055011:Ablation Techniques; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015179:Colorectal Neoplasms / Q000473:pathology*; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D033162:Incidental Findings; D008175:Lung Neoplasms / Q000000981:diagnostic imaging / Q000556:secondary* / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D049268:Positron-Emission Tomography; D011446:Prospective Studies; D000078702:Radiofrequency Therapy; D014057:Tomography, X-Ray Computed
chemical_list: D019788:Fluorodeoxyglucose F18