Comparing whole body 18F-2-deoxyglucose positron emission tomography and technetium-99m methylene diphosphonate bone scan to detect bone metastases in patients with breast cancer

Purpose: At present, bone metastases are usually assessed using conventional technetium-99m methylene diphosphonate whole-body bone scan, which has a high sensitivity but a poor specificity. However, positron emission tomography with F-18-2-deoxyglucose (FDG-PET) can offer superior spatial resolution and improved specificity. We attempted to evaluate the usefulness of FDG-PET for detecting bone metastases in breast cancer and to compare FDG-PET results with bone scan findings. Patients: The study group comprised 48 patients with biopsy-proven breast cancer and suspected of having bone metastases who underwent bone scan and FDG-PET to detect the bone metastases. The final diagnosis of bone metastases was established by operative, histopathological findings or during a clinical follow-up longer than I year by additional radiographs or following FDG-PET/bone scan findings showing progressive widespread bone lesions. Results: A total of 127 bone lesions including 105 metastatic and 22 benign bone lesions found by either FDG-PET or bone scan were evaluated. Using FDG-PET, 100 metastatic and 20 benign bone lesions were accurately diagnosed, and using bone scan 98 metastatic and 2 benign bone lesions were accurately diagnosed. The diagnostic sensitivity and accuracy of FDG-PET were 95.2% and 94.5%, and of bone scan were 93.3% and 78.7%, respectively. Conclusions: Our findings suggest that FDG-PET shows a similar sensitivity and a better accuracy than bone scan for detecting bone metastases in patients with breast cancer.