Solitary plasmacytoma. II: Solitary plasmacytoma of bone.

The clinical features and the results of treatment of twelve patients with solitary plasmacytoma of bone (SPB) are reported. The median age at presentation was 53 years and there was a predominance of males. Five patients have developed multiple myeloma (MM), for within three years and one after twelve years. Seven patients have not shown evidence of dissemination, and five are alive 1--15 years (median 9 years) after diagnosis. Two patients had metastases to local lymph nodes. There are no reliable criteria by which patients with truly SPB can be prospectively distinguished from those with occult MM, and it is recommended that all patients with apparent SPB should receive "curative" local therapy.