Extramedullary solitary plasmacytoma: Demonstrating the role of 18F-FDG PET imaging

An Extramedullary Plasmacytoma (EMP) is characterized by a neoplastic proliferation of clonal plasma cells outside the medullary cavity. EMPs are a rare occurrence compared to other malignant plasma cell disorders and account for approximately 3-5% of plasma-cell neoplasms. Although most cases of EMP are not immediately life threatening at diagnosis, EMPs can progress to Multiple Myeloma (MM) and thus, warrant monitoring. Currently, there are no standard guidelines for when and how to monitor patients who are diagnosed with or treated for a solitary plasmacytoma. We present a case of solitary EMP who was treated adequately and definitively but developed a distinct, non-contiguous subsequent solitary EMP and was only discovered due to surveillance¹⁸F-Fludeoxyglucose Positron Emission Tomography (¹⁸F-FDG) (PET) scan. Uniform surveillance guidelines should be developed and the potential benefits of PET and other imaging techniques as well as their cost should be considered.