Extramedullary plasmacytomas of the testes are extremely rare tumors,
especially when occurring in the absence of precocious or concurrent d
iagnosis of multiple myeloma. This is a case report of an 83-year-old
man with a solitary plasmacytoma of the left testis. Immunoperoxidase
studies, performed on histologic specimens after radical orchiectomy,
showed a monoclonal staining of intracellular immunoglobulin for IgG-l
ambda type. He has been well for more than 14 months with no evidence
of local recurrence or multiple myeloma.