title: Recognition of fibrous dysplasia of bone mimicking skeletal metastasis on 18F-FDG PET/CT imaging.
abstract: OBJECTIVE
  Fibrous dysplasia of bone (FDB) reveals intense 18F-FDG uptake mimicking metastases on 18F-FDG PET/CT. We reviewed sites of FDB revealed by 18F-FDG PET/CT imaging to allow identification of this abnormality.
  
  
  METHODS
  Eleven patients (7 male, 4 female, aged 16-78 years) were evaluated after 55 MBq (0.15 mCi)/kg 18F-FDG utilizing a 16-slice multiple detector CT (MDCT) whole-body PET scanner, with LOR algorithm 3D reconstruction. One- and 2-h imaging was performed in 9 patients. Standard uptake value (SUV) for each lesion, on early and delayed imaging, was calculated. Lesions were confirmed in 6 patients by biopsy. The PET images correlated with MDCT to establish the imaging characteristics.
  
  
  RESULTS
  Solitary lesions were found in 4 patients, two lesions in 1 patient, and in 6 patients there were multiple bone lesions. The SUV(early) ranged from 1.23 to 9.64 with an average of 3.76 ± 2.40. The SUV(delayed) ranged from 1.76 to 11.42 with an average of 4.51 ± 3.07. The SUV(delayed) decreased or increased slightly (-31% to 5%) in 6 of our patients, and increased significantly (11% to 39%) in 3. There was a negative correlation between SUVs and age, as well as the number of affected bones.
  
  
  CONCLUSIONS
  In our study, FDB had wide skeletal distribution with variability of 18F-FDG uptake and CT appearance. SUV in the delayed stage was seen to either decrease or increase on dual-time 18F-FDG PET scanning. It is very important to recognize the characteristics of this skeletal dysplasia to allow differentiation from skeletal metastasis.
authors.affiliation: National Key Discipline of Medical Imaging and Nuclear Medicine, Department of Nuclear Medicine, West China Hospital, Sichuan University School of Medicine, 37 Guo Xue Xiang, 610041, Chengdu, Sichuan, People's Republic of China. suminggang@sina.com
authors.forename: Ming Gang
authors.initials: MG
authors.lastname: Su
authors.forename: Rong
authors.initials: R
authors.lastname: Tian
authors.forename: Qiu Ping
authors.initials: QP
authors.lastname: Fan
authors.forename: Ye
authors.initials: Y
authors.lastname: Tian
authors.forename: Fang Lan
authors.initials: FL
authors.lastname: Li
authors.forename: Lin
authors.initials: L
authors.lastname: Li
authors.forename: An Ren
authors.initials: AR
authors.lastname: Kuang
authors.forename: John Howard
authors.initials: JH
authors.lastname: Miller
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001859:Bone Neoplasms / Q000175:diagnosis / Q000556:secondary; D003937:Diagnosis, Differential; D005260:Female; D005357:Fibrous Dysplasia of Bone / Q000175:diagnosis*; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013382:Subtraction Technique; D014057:Tomography, X-Ray Computed; D055815:Young Adult
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18