title: Role of [18F]FDG-PET/CT after radiofrequency ablation of liver metastases: preliminary results.
abstract: OBJECTIVE
  Focal metastasis may be treated with radiofrequency ablation (RFA), a low invasive method yet limited by the lack of direct evidence of radicality of treatment. We, hereby, aimed at assessing the role of positron emission tomography-computed tomography (PET/CT) with fluoride radiolabeled deoxy-glucose ([(18)F]FDG) in RFA treatment success evaluation and early diagnosis of local relapse of liver metastasis after RFA procedure.
  
  
  METHODS
  RFA was performed in nine patients on 12 liver metastasis, serially imaged through [(18)F]FDG-PET/CT and multidetector CT (MDCT) at 1, 3, 6, and 9 months after treatment. Eight lesions were also scanned with [(18)F]FDG-PET/CT at 1 week after treatment. Imaging analyses were performed on 47 [(18)F]FDG-PET/CT and 51 MDCT. Imaging reading outcomes were compared to each other and to biopsy tissue results when available.
  
  
  RESULTS
  In one case, [(18)F]FDG-PET/CT revealed radiotracer uptake at RFA site a week after procedure. Negative concordant outcome was obtained on eight lesions at 1 month after RFA, on eight cases at 3 months, on four at 6 months, and on two cases at 9 months. Extra-liver (peritoneal) disease was detected in one case by both [(18)F]FDG-PET/CT and MDCT. In seven cases, [(18)F]FDG-PET/CT revealed the presence of local recurrence earlier than MDCT. In no cases did MDCT detect local relapse earlier than [(18)F]FDG-PET/CT.
  
  
  CONCLUSIONS
  [(18)F]FDG-PET/CT may detect RFA treatment failure as well as local relapse after RFA earlier than MDCT.
authors.affiliation: Division of Nuclear Medicine, European Institute of Oncology, Via Ripamonti 435, 20141 Milan, Italy.
authors.forename: Laura L
authors.initials: LL
authors.lastname: Travaini
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Trifirò
authors.forename: Laura
authors.initials: L
authors.lastname: Ravasi
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Monfardini
authors.forename: Paolo
authors.initials: P
authors.lastname: Della Vigna
authors.forename: Guido
authors.initials: G
authors.lastname: Bonomo
authors.forename: Antonio
authors.initials: A
authors.lastname: Chiappa
authors.forename: Andrew
authors.initials: A
authors.lastname: Mallia
authors.forename: Mahila
authors.initials: M
authors.lastname: Ferrari
authors.forename: Franco
authors.initials: F
authors.lastname: Orsi
authors.forename: Giovanni
authors.initials: G
authors.lastname: Paganelli
mesh_terms: D055011:Ablation Techniques; D000230:Adenocarcinoma / Q000175:diagnosis / Q000378:metabolism / Q000556:secondary / Q000601:surgery; D014408:Biomarkers, Tumor / Q000378:metabolism; D001943:Breast Neoplasms; D018270:Carcinoma, Ductal, Breast / Q000175:diagnosis / Q000378:metabolism / Q000556:secondary / Q000601:surgery; D003110:Colonic Neoplasms; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008113:Liver Neoplasms / Q000175:diagnosis* / Q000378:metabolism / Q000556:secondary* / Q000601:surgery; D008297:Male; D049268:Positron-Emission Tomography; D000078702:Radiofrequency Therapy; D019275:Radiopharmaceuticals; D012004:Rectal Neoplasms; D014057:Tomography, X-Ray Computed
chemical_list: D014408:Biomarkers, Tumor; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18