Folliculotropic mycosis fungoides: challenging clinical, histopathological and immunohistochemical diagnosis

Mycosis fungoides is a cutaneous T-cell lymphoma with various clinical and pathological presentations. Early lesions are nonspecific, which hinders early diagnosis. The folliculotropic subtype is manifested as acneiform lesions, follicular papules or erythematous plaques mainly on the face, neck and upper trunk. Histopathology shows dense lymphocytic infiltrate surrounding and infiltrating the hair follicles. A case of difficult histopathological diagnosis with florid and unusual skin lesions mainly on the face is reported.