[Solitary breast metastasis from a plasmacytoma: fine needle cytological diagnosis]

We report a case of an extramedullary plasmocytoma of the breast in a 71 years old woman who suffered from six years of an osseous plasmocytoma. This lesion is rare and is associated with a serum monoclonal lambda gammopathy. A correct diagnosis of metastasis to the breast is important since the treatment of primary and secondary malignancies of the breast is different.