Diagnostic value of 18F-FDG PET/CT for differentiating multiple myeloma from bone metastases with undetermined origin / 中华核医学与分子影像杂志

ABSTRACT

Objective To investigate the value of 18F-FDG PET/CT for differentiating multiple myeloma from bone metastases with undetermined origin.Methods A retrospective study was performed on patients with multiple bone destructions and without extraosseous primary malignant tumor in 18F-FDG PET/CT imaging.A total of 26 patients (12 males,average age 55.4 years) with multiple myeloma and 20 patients (9 males,average age 50.2 years) with multiple bone metastases confirmed by biopsy or histopathology from January 2011 to December 2013 were included into this study.The characteristics of 18F-FDG PET/CT and urine Bence-Jones protein were used to establish the diagnostic criteria.Myeloma was diagnosed if two or more of the following conditions could be satisfiedmore than 10 bone lesions,osteolytic or mixed bone destruction,SUVmax＜4.0,and positive urine Bence-Jones protein.Two-sample t test and x2 test were used.Results The average number of bone lesions in multiple myeloma patients was 15.8,which was more than that (7.8) in patients with bone metastases.About 71.8％ (296/412) of bone lesions in multiple myeloma and 28.8％ (45/156) of bone metastases were osteolytic.The percentage of osteolytic lesions was significantly higher in multiple myeloma (x2=87.2,P＜0.05).The SUVmax of bone lesions of multiple myeloma and bone metastases were 3.81 ±2.17 and 5.82± 3.44 (t =8.29,P＜0.05) respectively.According to the diagnostic criteria,the sensitivity,specificity and accuracy of 18F-FDG PET/CT for the differentiation of myeloma from bone metastases were 88.5％ (23/26),85.0％ (17/20) and 87.0％ (40/46).Its diagnostic efficiency was higher than urine Bence-Jones protein (sensitivity65.4％ (17/26);x2=3.90) and original 18 F-FDG PET/CT evaluation (specificity10/18,accuracy64.1％ (25/39);x2 =3.99,6.12) respectively (all P＜0.05).Conclusion Combining the evaluation of structural properties and metabolism on 18F-FDG PET/CT with urine Bence-Jones protein level may provide additional value for the differentiation of multiple myeloma from bone metastases with undetermined origin.