Hyperpigmentation as a peculiar presentation of mycosis fungoides

ABSTRACT

Abstract Hyperpigmented mycosis fungoides is an extremely rare subtype of mycosis fungoides. It presents as multiple pigmented macules and patches without poikilodermatous changes and characterized by a CD8+ phenotype on immunohistochemistry. This report describes a typical case of hyperpigmented mycosis fungoides in a 62-year-old woman, who presented with a 7-year history of multiple hyperpigmented macules and patches on the trunk and right leg with progression over this half a year. Histology and immunohistochemical staining of skin samples confirmed the diagnosis of mycosis fungoides. She received psoralen plus ultraviolet A (PUVA) therapy. After an 8-week treatment, the erythematous changes cleared without recurrence during a 6-month follow-up period. An intractable hyperpigmented patch should raise the clinical suspicion of mycosis fungoides with sequential skin biopsy.