Background: A dedicated breast PET scanner with C-shaped detectors (C scanner) has been newly developed. The purpose of this study was to re-evaluate the diagnostic performance of high-resolution PET images with the new reconstruction conditions, obtained using this C scanner in breast cancer patients, and to compare the standardized uptake values (SUVs) of lesions obtained from the C scanner with those from whole-body PET/computed tomography (CT) (WB PET/CT).
Patients and methods: A total of 159 female patients with known or suspected breast carcinomas (total 188 lesions: 172 invasive carcinomas; eight noninvasive ductal carcinomas in situ; eight benign lesions) were analysed. All patients underwent a WB PET/CT scan 1 h after the injection of fluorine-18 fluorodeoxyglucose, followed by breast scanning using the C scanner. Attenuation-corrected and scatter-corrected images were reconstructed with new parameters.
Results: Using the C scanner, 146 of 180 malignant lesions including five ductal carcinomas in situ were detected, 11 lesions were not detected, and the remaining 23 lesions were outside the field of view. The lesion-based sensitivity of the C scanner was 81.1%, and this was increased to 93.0% after excluding lesions outside the field of view; the sensitivity of WB PET/CT was 90.4%. The average maximum SUV of lesions obtained using the C scanner was 9.8±7.0, which was ∼1.6-fold larger than that obtained using WB PET/CT (6.1±4.2).
Conclusion: There was no significant difference in breast cancer detectability in this population. The C scanner demonstrated ∼1.6-fold larger maximum SUV than WB PET/CT.