FIGURE 4.

A 66-year-old woman with a history of primary right-sided breast cancer treated with right mastectomy and implant reconstruction presents for routine follow-up imaging. ¹⁸F-FDG PET/CT images (A, MIP; B and C, axial PET, fused PET/CT, and CT) demonstrated focal intense uptake in the medial aspect of the right breast adjacent to the implant in keeping with disease recurrence (B, arrow). There was also intense uptake in a nonenlarged left subpectoral lymph node (C, arrow). Further questioning revealed the patient had received the COVID-19 vaccine in the left arm less than 3 weeks earlier. Further research on clarifying the expected time course of axillary lymph node FDG avidity and associated SUV values on PET/CT is needed, especially as new COVID-19 vaccinations to target emerging variants may be introduced in the future. This will also ensure these patients are appropriately managed going forward.