• ABSTRACT
    • This study aimed to review the clinical features and outcome of 53 patients with solitary plasmacytoma managed at our Institution between 1976 and 2012. Thirty-five patients had bone solitary plasmacytoma and 18 extramedullary solitary plasmacytoma. Tumour sizes were larger in patients with bone involvement (P = 0·003). Treatment consisted of local radiotherapy (n = 26), radiotherapy + chemotherapy (n = 15), surgery (n = 4) and chemotherapy (n = 8); the local control rate was 94·3%. Progression to multiple myeloma was recorded in 20/35 (57·1%) patients with bone involvement and in 1/18 (5·5%) patients with extramedullary disease (P = 0·0003). The 5-year overall survival (OS) rate was 78·4%; bone solitary plasmacytoma patients had a significantly worse OS (71·9% vs. 88·2%, respectively; P = 0·029) and 5-year progression-free survival (PFS; 53·0% vs. 88·5%; P = 0·0003) compared to extramedullary solitary plasmacytoma patients. On univariate analysis, bone disease and size (≥5 cm) impacted negatively on PFS (P = 0·0027 and P = 0·04, respectively). Bone disease also affected OS (P = 0·04). In multivariate analysis bone location was the only independent prognostic factor for PFS (P = 0·0041) and OS (P = 0·021). Patients with bone solitary plasmacytoma have a significantly worse prognosis than extramedullary solitary plasmacytoma cases.