The Prognostic Indicators of Progression From Solitary Plasmacytoma to Multiple Myeloma: A Narrative Review.

Solitary plasmacytomas (SPs), encompassing both solitary bone plasmacytoma (SBP) and extramedullary plasmacytoma (EMP), are rare plasma cell neoplasms that carry a risk of progression to multiple myeloma (MM). This review synthesizes current literature on the prognostic indicators predictive of such progression. High-risk cytogenetic abnormalities have been consistently linked to faster transition to MM. Other factors, such as tumor size, age, and persistent M-protein levels after treatment, are also prognostic factors. While radiotherapy remains the cornerstone of treatment, its curative potential is influenced by these indicators. Time to progression to MM is highly variable. This review highlights the need for standardized risk stratification systems to guide surveillance and treatment decisions in patients with SP.