Clinical value of SPECT/CT fusion imaging in diagnosing metastatic bone lesions in breast cancer

Objective: To evaluate the diagnostic value of SPECT/CT fusion imaging in indeterminate lesions on ⁹⁹Tc^m-MDP whole-body bone scan in patients with breast cancer. Methods: 210 bone lesions of 132 patients with breast cancer, for whom the natures of the lesions were unable to be determined by the ⁹⁹Tc^m-MDP whole-body bone scan, were examined by the SPECT/CT fusion imaging simultaneously. The natures of the lesions were eventually confirmed by pathology and clinical follow-up. The accuracy, sensitivity, specificity, positive predictive value and negative predictive value of SPECT/CT fusion imaging for diagnosing bone-metastases were calculated. In addition, the diagnostic accuracy of SPECT/CT fusion imaging for bone lesions in various parts of the body was also analyzed. Results: (1) Of 210 bone lesions, 82 of bone metastases and 112 benign bone lesions were correctly diagnosed by SPECT/CT fusion imaging. The diagnostic accuracy, sensitivity, specificity, positive prediction value and negative prediction value was 92.4% (194/210), 94.3% (82/87), 91.1% (112/123), 88.2% (82/93), 95.7% (112/117), respectively. (2) The diagnostic accuracy of ⁹⁹Tc^m-MDP SPECT/CT for spinal bone lesions were significantly higher than that for rib lesions (95.9% versus 83.7%, χ² = 7.81, P < 0.05). Conclusions: (1) 92.4% bone lesions in patients with breast cancer, which can not determined on ⁹⁹Tc^m-MDP whole-body bone scan, can be diagnosed by SPECT/CT fusion imaging accurately. (2) Diagnositic compliance rate of SPECT/CT fusion imaging is different in different parts with obscure lesion, which is the highest in the spine, the minimum in ribs. (authors)