Granulomatous Mycosis Fungoides

Granulomatous Mycosis Fungoides (MF): About 4% of cases of otherwise typical MF show a granulomatous component in a background of atypical lymphocytes. This can range from aggregates of epithelioid histiocytes to clusters of multinucleated giant cells to well-formed sarcoid-type granulomas. Granulomas are considered to be an immune response to the tumor. Their impact on prognosis is uncertain. Granulomatous reaction can also be seen in folliculotropic MF following rupture of the hair follicles.

This image shows well-developed granulomatous inflammatory infiltrate with a few multinucleated giant cells in a background of atypical lymphocytes, filling up the dermis and subcutis.