The clinical value of the qualitative and semi-quantitative 18F-FDG PET/CT in the detection of primary breast cancer and lymph node metastasis

Objective: The purpose of this study was to assess the diagnostic efficiency of the qualitative and semi-quantitative analyses of 18F-fluorodeoxyglucose (FDG) PET/CT for staging primary breast cancer. Methods: This prospective study included 39 patients. Of the 39 cases, 24 were primary, breast cancer, 15 were benign breast lesions. Patients underwent regional FDG PET/CT scanning covering bilateral breasts and axilla. All primary breast cancer lesions were confirmed by pathologic results of surgery. Twenty-four cases with benign lesions were established according to the results of surgery or clinical follow-up for at least 12 months. The qualitative and semi-quantitative 18F-FDG uptake results were used for T staging and N staging of breast cancer. SPSS 11.5 was used for data analysis. Results: When using SUVmax>4.5 as the cutoff value or SUVmax>x-bar + 2s of contra-lateral normal breast SUVmax as the cutoff value combined CT malignant signs for initial diagnosis, the sensitivity, specificity of diagnosing breast malignant lesion were 96.0% (24/25), 63.2% (12/19), respectively. By using threshold of SUVmax>2.5, the sensitivity, specificity were 60% (6/10), 92.3 % (12/13) respectively for staging regional lymphadenopathy. Conclusion: For staging primary breast carcinoma with FDG PET/CT, higher sensitivity could be acquired when using SUVmax>4.5 or SUVmax>x-bar + 2s of contra-lateral normal breast SUVmax as the cutoff value combined with CT malignant signs. (authors)