Granulomatous reactions in mycosis fungoides.

Granulomatous reaction characterized by the formation of noncaseating accumulations of epithelioid histiocytes and multinucleated giant cells of the foreign-body type is a rare, poorly understood, and generally ignored phenomenon seen in various types of lymphoma. Its presence in cutaneous infiltrates of mycosis fungoides is equally unusual, but some favorable prognostic significance has been ascribed to it previously. In this paper, four patients with typical mycosis fungoides and granulomas demonstrated histologically in their cutaneous infiltrates are presented. All four died of disseminated disease with evidence of central nervous system involvement in three of them. These clinical histories lend no support to the notion that granulomatous mycosis fungoides is a benign variant of this lymphoma. Relevant literature is reviewed and discussed.