Abstract
A primary anaplastic large cell lymphoma of the breast is presented. A 19-year-old man presented with a swelling of the breast of a short duration. This was not associated with lymphadenopathy or ulceration of the skin. Biopsy of this lesion showed the presence of large, anaplastic cells with multinucleation and markedly indented, ‘embryo-like’ nuclei. The tumor cells were present within breast tissue and surrounded breast ducts. A panel of immunohistochemical markers showed these large cells to be CD30, CD3, and EMA positive. This case emphasizes the occurrence in the breast of anaplastic large cell lymphoma as a primary tumor. It should be considered in the differential diagnosis of anaplastic tumors occurring in the breast, and pertinent immunohistochemistry is recommended.