Diagnostic performance of 18F-fluorodeoxyglucose PET/CT and bone scintigraphy in breast cancer patients with suspected bone metastasis

Background We prospectively compared the diagnostic accuracies of PET/CT and BS in patients with suspected bone metastases from breast cancer. Methods This single-institution prospective study included consecutive patients with suspected bone metastases from biopsy-proven breast cancer seen at Tokai University Hospital between September 2011 and March 2014. Inclusion criteria included suspicions for bone metastases (bone pain, elevated alkaline phosphatase, elevated tumor markers, or suspected bone metastases by BS). Two nuclear medicine physicians evaluated PET/CT and BS images. Results Thirty patients were initially enrolled in this study. Two were excluded from the analyses because they declined to undergo imaging during follow-up. PET/CT successfully detected bone metastases in all 10 patients finally diagnosed with the condition, whereas BS identified 2. The two methods were not highly concordant in detecting osseous metastases. In 19 of 28 paired studies (68 %), 2 (10 %) were positive for metastasis, and 17 (90 %) were negative. Nine occurrences (32 %) were discordant; of these, 2 were PET/CT positive and BS negative; 5 were PET/CT positive and BS equivocal; one was PET/CT negative and BS equivocal, and one was PET/CT equivocal and BS negative. Conclusions Our results indicated that PET/CT was superior to BS for the diagnosis of bone metastases. On the basis of the results of previous studies as well as ours, PET/CT could replace BS as the initial modality to detect bone metastases in patients suspected for the condition.