HISTOLOGIC EVALUATION OF THE LONG-TERM EFFECTS OF TRETINOIN ON PHOTODAMAGED SKIN

Sustained improvement with prolonged topical tretinoin for photodamage d skin has been well documented for up to 22 months of continuous trea tment. We now report long-term (4 years) histologic effects of topical tretinoin in photodamaged skin of 27 patients, the longest study to d ate. The observed decreases in dermal elastin content and perivascular inflammation and increase in epidermal mucin in facial biopsies obtai ned after up to 4 years of treatment may be partly responsible for the continued clinical improvement. Furthermore, the study shows that the re are no untoward effects on keratinocytes or melanocytes during long -term use of topical tretinoin.