Recognition of fibrous dysplasia of bone mimicking skeletal metastasis on 18F-FDG PET/CT imaging.
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.
Su
Ming Gang
MG
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
Tian
Rong
R
Fan
Qiu Ping
QP
Tian
Ye
Y
Li
Fang Lan
FL
Li
Lin
L
Kuang
An Ren
AR
Miller
John Howard
JH
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
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18