Objective: To define the optimal treatment and outcomes for patients with solitary plasmacytoma of bone and soft tissue.

Methods: Review of the literature.

Results: Solitary plasmacytomas are uncommon and account for less than 5% of plasma cell neoplasms. Solitary plasmacytomas of bone (SPB) usually occur in the vertebra and skull and are more common than extramedullary plasmacytomas (EMP) that almost always arise in the head and neck and may spread to regional lymph nodes. The optimal treatment is moderate-dose radiotherapy (40-50 Gy) and occasionally surgery. Adjuvant chemotherapy does not improve survival. Patients with EMP have a relatively low risk of progressing to multiple myeloma and have improved survival compared with those who present with SPB.

Conclusions: Solitary plasmacytoma is an uncommon neoplasm that often arises in the head and neck. Optimal treatment is moderate-dose radiotherapy. Prognosis is relatively good and is better for patients with EMP compared with those presenting with SPB.