Breast cancer imaging studies with a variable field of view PET cameral

This is a study of the FDG breast career imaging capability of the prototype high resolution multi-ring variable field of view PET scanner developed at the University of Texas MD Anderson Cancer Center (MDAPET). For the primary-lesion-imaging test, four small phantom lesions embedded into two different size cylindrical breast phantoms were imaged using the breast-mode of the camera. Data for the hot lesion phantoms and the warm background were taken separately. Then, before image reconstruction, two sets of data were selectively combined to generate the data for the desired SUV. The cylindrical lesions have diameter and height of 3-6 mm with standard uptake value (SUV) ranging from 2.3 to 15. For the axillary-lesion imaging test, four small hot lesion phantoms taped to the axillary area of a torso phantom were imaged using a whole-body mode of the camera. To create a realistic background a 68-kg volunteer injected with 3.5 mCi of FDG were also imaged. The two sets of data were selectively combined to generate the sinogram data for the desired SUV. The lesions were 4-11.5 mm with SUV ranging from 2.5 to 17. The primary breast lesion imaging results show that a 3 mm lesion can be detected in both the small (phi=11.5 cm) and large (phi 16 cm) breast phantoms when SUV is greater than 2.5. In the whole body mode, axillary lesions of 6 mm can be detected for lesion SUV of 5 or more.