Bullous mycosis fungoides: a case report.

Mycosis fungoides (MF) on extremely rare occasions is associated with vesiculobullous eruptions. We describe a 74-year-old man with previous documented histopathologic diagnosis of poikilodermic-type MF who recently developed flaccid acral bullae on erythematous MF plaques and on normal appearing skin. Histopathology and direct immunofluorescent studies revealed extensive lichenoid changes with intraepidermal bullae. Atypical lymphocyte infiltration was present at the dermoepidermal junction, in bulla fluid, and on the peripheral blood smear, but in lymph node and bone marrow tissue specimens atypical lymphocytes were absent. The plausible cause of these blister formations in cutaneous lymphoma bullosa may be from excessive epidermotropism or toxicity of the tumoral infiltrate.