Immunoglobulin-A producing probably primary lymphoma of the breast.

A breast tumour from a 65-year old woman was found to be a primary non-Hodgkin lymphoma, a very rare primary malignancy in this location. The lymphoma was of a diffuse histiocytic type according to the classification of Rappaport, or polymorphic immunocytoma according to the Kiel classification. Immunohistochemistry, not previously reported for breast lymphomas, revealed the production of IgA. In the serum this appeared as an IgA M-component which was greatly reduced after tumour removal. Immunological properties of primary breast lymphomas are reviewed, we suggest further extended studies with the immunohistochemical use of marker substances for the evaluation of prognosis.