title: Histological effects of tazarotene 0.1% cream vs. vehicle on photodamaged skin: a 6-month, multicentre, double-blind, randomized, vehicle-controlled study in patients with photodamaged facial skin.
abstract: BACKGROUND
  Topical tazarotene has been shown to offer efficacy in ameliorating multiple effects of photodamage.
  
  
  OBJECTIVE
  To evaluate the histological effects of tazarotene cream on photodamaged skin.
  
  
  METHODS
  In this multicentre, double-blind, randomized, vehicle-controlled study, 50 patients with photodamaged facial skin (at least mild fine wrinkling and mottled hyperpigmentation, with at least one of these being moderate) were randomized to apply tazarotene 0.1% cream or vehicle cream to their face, once daily for 24 weeks.
  
  
  RESULTS
  Blinded assessments showed that tazarotene was less likely than vehicle to be associated with an increase in keratinocytic and melanocytic atypia, and more likely than vehicle to be associated with a reduction in atypia. Between-group comparisons in distribution of change from baseline categories of severity were in favour of tazarotene (P = 0.055 for keratinocytic atypia, P = 0.034 for melanocytic atypia, and P < 0.001 for the number of granular cell layers). Compared with vehicle, tazarotene was associated with an increase in epidermal polarity (P = 0.008) and epidermal thickness (P = 0.012), and a tendency for stratum corneum compaction. Tazarotene was also associated with widened intercellular spaces (reported as epidermal oedema) relative to vehicle (P < 0.001).
  
  
  CONCLUSIONS
  Treatment of photodamaged skin with tazarotene is associated with an amelioration of keratinocytic and melanocytic atypia, an improvement in epidermal polarity, and an increase in epidermal thickness.
authors.affiliation: University of California-Irvine and South Coast Medical Center, Laguna Beach, CA, USA.
authors.forename: L A
authors.initials: LA
authors.lastname: Machtinger
authors.forename: K
authors.initials: K
authors.lastname: Kaidbey
authors.forename: J
authors.initials: J
authors.lastname: Lim
authors.forename: K H
authors.initials: KH
authors.lastname: Loven
authors.forename: T E
authors.initials: TE
authors.lastname: Rist
authors.forename: D C
authors.initials: DC
authors.lastname: Wilson
authors.forename: D D
authors.initials: DD
authors.lastname: Parizadeh
authors.forename: J
authors.initials: J
authors.lastname: Sefton
authors.forename: J M
authors.initials: JM
authors.lastname: Holland
authors.forename: P S
authors.initials: PS
authors.lastname: Walker
mesh_terms: D000328:Adult; D000368:Aged; D004311:Double-Blind Method; D005148:Facial Dermatoses / Q000188:drug therapy* / Q000473:pathology; D005260:Female; D006801:Humans; D017495:Hyperpigmentation / Q000188:drug therapy* / Q000473:pathology; D015603:Keratinocytes / Q000473:pathology; D007641:Keratolytic Agents / Q000009:adverse effects / Q000627:therapeutic use*; D008297:Male; D008544:Melanocytes / Q000473:pathology; D008875:Middle Aged; D009539:Nicotinic Acids / Q000009:adverse effects / Q000627:therapeutic use*; D014677:Pharmaceutical Vehicles / Q000009:adverse effects / Q000627:therapeutic use; D012720:Severity of Illness Index; D015595:Skin Aging / Q000187:drug effects* / Q000473:pathology; D016896:Treatment Outcome; D012176:Retinoids
chemical_list: D007641:Keratolytic Agents; D009539:Nicotinic Acids; D014677:Pharmaceutical Vehicles; C086827:tazarotene; D012176:Retinoids