title: Follicular mycosis fungoides: variability of a rare entity.
abstract: OBJECTIVE
  Three patients with follicular mycosis fungoides (FMF), a rare variant of folliculotropic cutaneous T-cell lymphoma, are discussed. Follicular involvement in cutaneous T-cell lymphoma commonly presents clinically with alopecia, follicular cysts, or comedo-like lesions usually associated with follicular mucinosis and strong epidermotropism. In contrast, FMF, in a strict sense, has been defined as a lymphocytic infiltration of hair follicles in the absence of both epidermal invasion and follicular mucin.
  
  
  CONCLUSIONS
  Case 1 shows a clinically stable form of FMF characterized by circumscribed alopecia and its persistent resistance to topical therapeutic approaches. In contrast, Cases 2 and 3 demonstrate that classic mycosis fungoides lesions and FMF can occur simultaneously and that transitions occur from mycosis fungoides to FMF and vice versa. These observations strengthen the concept that FMF and mycosis fungoides represent just two variants of one entity of cutaneous T-cell lymphoma. In Case 3, rapid progression into tumor-stage mycosis fungoides and the follicular infiltration was controlled with bexarotene.
  
  
  CONCLUSIONS
  Because it was previously suggested that FMF may have a worse prognosis compared with classic mycosis fungoides, this impressive response to bexarotene is of great clinical interest and may spark new studies employing this novel retinoid for FMF treatment.
authors.affiliation: Department of Dermatology, University of Regensburg, Franz-Josef-Strauss-Allee 11, D-93053, Regensburg, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Roeschm
authors.forename: Verena
authors.initials: V
authors.lastname: Schleyer
authors.forename: Michael
authors.initials: M
authors.lastname: Landthaler
authors.forename: Thomas
authors.initials: T
authors.lastname: Vogt
mesh_terms: D000328:Adult; D000368:Aged; D016588:Anticarcinogenic Agents / Q000627:therapeutic use; D000077610:Bexarotene; D005260:Female; D018859:Hair Follicle; D006801:Humans; D008297:Male; D008875:Middle Aged; D009182:Mycosis Fungoides / Q000188:drug therapy / Q000473:pathology*; D012878:Skin Neoplasms / Q000188:drug therapy / Q000473:pathology*; D013764:Tetrahydronaphthalenes / Q000627:therapeutic use
chemical_list: D016588:Anticarcinogenic Agents; D013764:Tetrahydronaphthalenes; D000077610:Bexarotene