Abstract
Solitary plasmacytoma (SP) of the bone is a localized neoplasm of plasma cells that can involve the jaw. Epstein-Barr virus (EBV)-positive SP has been documented in immunocompetent individuals; however, its clinicopathological features and prognostic implications remain to be fully clarified. We report a case of EBV-positive SP of the maxilla in a 74-year-old partially edentulous man who presented with swelling in the left posterior maxilla. The lesion measured approximately 30 mm and was covered by intact mucosa. Histopathological examination and systemic evaluation confirmed EBV-positive SP localized to the maxilla. The patient initially received radiotherapy without effect. Subsequently, chemotherapy with ixazomib, lenalidomide, and dexamethasone was administered, resulting in a complete response. No local recurrence was observed after 2 years and 6 months of follow-up. This case highlights the potential for chemotherapy in managing radiotherapy-resistant EBV-positive SP. Further studies are warranted to better understand the pathogenesis and treatment strategies for this rare condition.