Solitary plasmacytoma. I: Extramedullary soft tissue plasmacytoma.

The details of 16 patients with extramedullary plasmacytoma are presented. All but one presented with localized disease, and all were treated successfully by radiotherapy. Only one patient developed local recurrence and only one has developed disseminated disease. Radiotherapy is recommended as the primary treatment of choice for these localized radiosensitive tumors. It is suggested that the good prognosis of plasmacytomas of the head and neck, in contrast to plasmacytomas arising at other sites, is related to the observation that a high proportion of these tumors are localized at the time of diagnosis and that very large primary tumors are uncommon.