RESUMO
BACKGROUND: Topical tazarotene has been shown to offer efficacy in ameliorating multiple effects of photodamage. OBJECTIVES: 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.