Figure 3.

Two cases demonstrating how incidental breast uptake, which were both later proven to be carcinoma, can have highly variable FDG uptake. (a, b) are axial PET and CT images respectively from a 69-year-old female who had a PET/CT as part of staging for a previously removed melanoma. No other sites of melanoma were identified; however; there was low-grade uptake (SUVmax 1.8) in the axillary tail of the left breast (arrow) in (a) which localized to a soft-tissue nodule, on the CT (b). This was confirmed as invasive ductal adenocarcinoma on histology. In contrast, there was very intense uptake (SUVmax 19.1), axial PET only image, (c) in the breast of a 73-year-old female who had a PET/CT for potential myeloma. This localized to a breast soft-tissue lesion demonstrated on the CT only image, (d) which was also later confirmed as primary breast carcinoma. FDG, fluodeoxyglucose; PET, positron emission tomography; SUV, standardized uptake value.