Guidelines on the diagnosis and management of solitary plasmacytoma of bone and solitary extramedullary plasmacytoma.

Most patients with plasma cell neoplasia have generalized disease at diagnosis, i.e. multiple myeloma (MM). However, a minority (<5%) of patients with plasma cell malignancies present with either a single bone lesion, or less commonly, a soft tissue mass, of monoclonal plasma cells: solitary bone plasmacytoma (SBP) or extramedullary plasmacytoma (SEP). SBP has a high risk of progression to MM and on magnetic resonance imaging (MRI) examination at least 25% of patients with an apparent solitary lesion have evidence of disease elsewhere (Moulopoulos et al, 1993). In contrast, SEP is nearly always truly localized and has a high cure rate with local treatment. The diagnosis and management of patients with solitary plasmacytoma requires the same range of clinical and laboratory expertise as for patients with MM (UK Myeloma Forum, 2001). The primary treatment for most patients will be radiotherapy, but surgery may also be required, where close liaison among the haematologist, radiotherapist and surgeon is crucial for planning optimum care.