Plasmacytoma of the thyroid gland.

Solitary plasmacytoma of the thyroid is very rare. Thus far, only 12 cases have been reported in literature. This report describes the clinical and histological features of two additional cases. One patient developed bone metastases 1 month after diagnosis and died 17 months later. The second patient is alive with no evidence of disease, 19 months after diagnosis. At the present time there are insufficient data to assess the prognosis in any single case.