Abstract
1203
Objectives A newly developed PET scanner (mPET), dedicated for breast imaging, has been installed. The purpose of this study was to evaluate the feasibility of PET mammography by mPET in patients with breast cancer.
Methods There were two types of mPET scanners, O-shaped and C-shaped. The O-shaped scanner was designed for scanning in prone position, and the C-shaped one in a sitting posture. The spatial resolution of each device was approximately 1 mm. A total of 11 female patients (33 - 77 y.o., mean 58.2 y.o.) with histologically proven breast cancer, including recurrence in one patient, were enrolled in this study. All patients underwent a whole body PET/CT scan for staging at one hour post-injection of 185 MBq of FDG, followed by breast scanning using the mPET scanners with the max acquisition time of 10 min. Depiction of lesions and image quality were assessed for six datasets, reconstructed by 1, 2, 4, 6, 8, 10-min acquisition data.
Results There were 12 lesions (Right:Left=5:7) in 11 patients, which were all visualized on PET/CT. The size of these lesions was ranging from 14 to 38 mm. In the O-shaped scanner, 11 of 12 lesions were depicted more clearly than by a whole PET/CT scanner, while one lesion was missed due to the out of scanning range. The C-shaped scanner was applied for 10 patients. Nine of 11 lesions were depicted, but the remaining two lesions were out of range in spite of struggle of positioning. All missed lesions located in the chest wall. In the analysis of image quality, all depicted lesions were visualized after one minute acquisition, but they were clearer with the increase of acquisition time. As for the noise of surrounding tissue, images were considered almost equivalent after six minutes acquisition.
Conclusions Our preliminary study demonstrate that the mPET scanners were feasible in clinical, and can depict lesions with higher spatial resolution. However, further evaluation is needed to get proper scanning range