Report of a rare case of bullous mycosis fungoides

Mycosis fungicides (MF), on extremely rare occasions, can be associated with vesiculobullous eruptions. We describe a 74-year-old man with previous documented histopathologic diagnosis of poikilodermic type of MF who recently developed some flaccid acral bullae on erythemoatous MF plaque and normal skin. Histopathology and direct immunoflourscence studies revealed extensive lichenoid changes with intraepidermal bulla. Atypical lymphocyte infiltration was presented in dermoepidermal junction and bulla fluid and peripheral blood smear, but absent in lymph node and bone narrow tissue specimens. The plausible cause of blister formation in cutaneous lymphoma bullosa may be due to excessive epidermotropism or toxic effects of cytokines secrected by the tumoral infiltrate.