Solitary Plasmacytoma: a Review of Diagnosis and Management

Solitary plasmacytoma is a rare plasma cell dyscrasia, classified as solitary bone plasmacytoma or solitary extramedullary plasmacytoma. These entities are diagnosed by demonstrating infiltration of a monoclonal plasma cell population in a single bone lesion or presence of plasma cells involving a soft tissue mass, respectively. Both diseases represent a single localized process without significant plasma cell infiltration into the bone marrow or evidence of end organ damage. Clinically, it is important to classify plasmacytoma as having completely undetectable bone marrow involvement versus minimal marrow involvement. Here, we discuss the diagnosis, management, and prognosis of solitary plasmacytoma. There have been numerous therapeutic advances in the treatment of multiple myeloma over the last few years. While the treatment paradigm for solitary plasmacytoma has not changed significantly over the years, progress has been made with regard to diagnostic tools available that can risk stratify disease, offer prognostic value, and discern solitary plasmacytoma from quiescent or asymptomatic myeloma at the time of diagnosis. Despite various studies investigating the use of systemic therapy or combined modality therapy for the treatment of plasmacytoma, radiation therapy remains the mainstay of therapy. Much of the recent advancement in the management of solitary plasmacytoma has been through the development of improved diagnostic techniques.