Plasmacytoma—current approach to diagnosis and management

About 3-5% of patients with plasma cell dyscrasias present with either a single bone lesion, or less commonly, a soft tissue mass made up of monoclonal plasma cells without evidence of bone marrow involvement or end-organ damage known as a solitary plasmacytoma (SP). SP of bone mostly occurs in axial skeleton, while it most often affects the head and neck region in case of extramedullary tumors. Their median age is 55 years and mostly present with bony pain, spinal cord, or nerve root compression. A whole body (WB) or spine and pelvic magnetic resonance imaging (MRI) scan or WB fluorodeoxyglucose-positron emission tomography (FDG-PET) scan should be included in staging of these patients. The standard of care for SP is radiotherapy (RT) given with curative intent. Surgery may be required for patients with retropulsed bone, structural instability of the bone, or rapidly progressive neurological symptoms from spinal cord compression. The role of adjuvant RT after complete surgical resection, adjuvant chemotherapy, or adjuvant bisphosphonates is not well defined and hence not recommended.