title: Pilotropic cutaneous T-cell lymphoma without mucinosis. A variant of mycosis fungoides? French Study Group of Cutaneous Lymphomas.
abstract: BACKGROUND
  In the course of mycosis fungoides, pilofollicular manifestations without mucinosis (papules, keratoses, comedones, or epidermal cysts) are rare (15 cases reported). Therefore, histological and clinical diagnoses may be difficult. The clinical course and histopathological and immunohistochemical findings in 9 patients are described.
  
  
  METHODS
  Pilofollicular lesions were present at the onset (n = 3), before (n = 3), or during a relapse of mycosis fungoides (n = 3). Comedones and epidermal cysts were most frequent (n = 5). They disappeared with lymphoma therapy (n = 4), therapy with isotretinoin (n = 3), or spontaneously (n = 1), or they persisted (n = 1). Clues to the histopathological diagnosis consisted of pilotropism of the infiltrate with minor alteration of the hair follicle walls. The infiltrate was monomorphous and composed of sezariform CD4+ lymphocytes. Pilotropic or peripilofollicular infiltrates, or the absence of infiltrate, were detected in consecutive biopsy specimens obtained from the same patient. The keratinocyte expression of intercellular adhesion molecule type 1 was observed in the hair follicle bulb in front of the pilotropic infiltrate but not in the epidermis. No staining was observed in biopsy specimens of 6 of 7 patients with follicular mucinosis, of folliculitis lesions, or of normal hair follicles.
  
  
  CONCLUSIONS
  Our findings indicate the role of adhesion molecules in pilotropism leading to mechanical obstruction of the follicle by tumoral cells followed by hyperkeratosis and cyst formation. It remains to be determined if the expression of intercellular adhesion molecule type 1 is the cause or the consequence of pilotropism. By becoming more aware of it, this variant of mycosis fungoides is probably not so rare.
authors.affiliation: Department of Pathology, University of Bordeaux, France.
authors.forename: B
authors.initials: B
authors.lastname: Vergier
authors.forename: M
authors.initials: M
authors.lastname: Beylot-Barry
authors.forename: C
authors.initials: C
authors.lastname: Beylot
authors.forename: A
authors.initials: A
authors.lastname: de Mascarel
authors.forename: M
authors.initials: M
authors.lastname: Delaunay
authors.forename: A
authors.initials: A
authors.lastname: de Muret
authors.forename: L
authors.initials: L
authors.lastname: Vaillant
authors.forename: M C
authors.initials: MC
authors.lastname: Tortel
authors.forename: F
authors.initials: F
authors.lastname: Grange
authors.forename: M
authors.initials: M
authors.lastname: Bagot
authors.forename: L
authors.initials: L
authors.lastname: Laroche
authors.forename: J
authors.initials: J
authors.lastname: Wecshler
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009182:Mycosis Fungoides / Q000145:classification / Q000473:pathology*; D012878:Skin Neoplasms / Q000145:classification / Q000473:pathology*