title: Juvenile-onset hypopigmented mycosis fungoides mimicking vitiligo.
abstract: BACKGROUND
  Mycosis fungoides (MF) is the most common form of cutaneous T-cell lymphoma and typically affects older adults. It is estimated that less than 5% of MF cases are of juvenile onset. An uncommon hypopigmented variant of MF exists, which has been more commonly observed in dark-skinned individuals and predominantly in juvenile-onset cases.
  
  
  METHODS
  We describe an 8-year-old otherwise healthy Hispanic male who, by 6 months of age, had developed asymptomatic hypopigmented patches on the lower legs, thighs, and buttocks, which have evolved over the past 7 years. This condition had previously been misdiagnosed as vitiligo. Recent immunohistologic and molecular biology studies are consistent with MF.
  
  
  CONCLUSIONS
  Given that hypopigmented MF is an uncommon condition, it may not be clinically suspected in the pediatric population. Histopathologic, immunophenotypic, and/or molecular biologic studies are sometimes equivocal, with findings similar to inflammatory dermatoses or autoimmune vitiligo, which may initially lead to a misdiagnosis, as in this patient's case.
authors.affiliation: Faculty of Medicine, Department of Pathology and Laboratory Medicine, Division of Dermatology, University of Calgary, Calgary, AB, Canada. jtvngo@ucalgary.ca
authors.forename: Jennifer T
authors.initials: JT
authors.lastname: Ngo
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Trotter
authors.forename: Richard M
authors.initials: RM
authors.lastname: Haber
mesh_terms: D002648:Child; D003937:Diagnosis, Differential; D006801:Humans; D017496:Hypopigmentation / Q000473:pathology; D008297:Male; D009182:Mycosis Fungoides / Q000175:diagnosis* / Q000473:pathology; D012878:Skin Neoplasms / Q000175:diagnosis* / Q000473:pathology; D014820:Vitiligo / Q000175:diagnosis*