Solitary Plasmacytoma and its Progression into Multiple Myeloma – A Case Report

Introduction: Solitary plasmacytoma (SP) is a rare plasma cell dyscrasia characterized by localized monoclonal plasma cell proliferation without systemic involvement. Although radiotherapy remains the standard treatment, progression to multiple myeloma (MM) is a recognized risk. Case Report: We report a case of SP initially presenting as a localized bone lesion, diagnosed through imaging, histopathology, and laboratory evaluation. The patient underwent standard treatment and was closely followed. Over time, the disease progressed to MM, confirmed by clinical deterioration, laboratory findings, and radiological evidence. Conclusion: This case highlights the aggressive potential of SP and reinforces the importance of prolonged surveillance for early detection of progression to MM.