Comparative study between fractional carbon dioxide laser versus retinoic acid chemical peel in the treatment of acanthosis nigricans

Background: Acanthosis nigricans (AN) is a common dermatological issue with several therapeutic modalities to treat. Despite retinoid is the first drug of choice in the treatment, the fractional-ablative carbon dioxide (CO2) laser has revealed as a promising procedure for the management of neck-AN, outstanding to its ability for superficial ablation of the skin surface, with trans-epidermal melanin elimination. Objectives: To decide whether fractional-ablative CO2 laser or retinoic acid (5%) peel is the more effective and safe choice for AN treatment. Methods: In this study, twenty Egyptian cases with neck-AN were enrolled, where each case was exposed to four sessions with 2 weeks apart of both fractional CO2 laser on the right half of the neck and retinoic acid peel on the left half of the neck. Cases were assessed by a scoring system: Acanthosis Nigricans Area and Severity Index (ANASI) score, two blinded dermatologists, and dermoscopically before and one month after treatment. Results: We found a highly statistically significant improvement among both treated groups regarding (ANASI) score and dermatologist's assessments. Bedside, the degree of sulci cutis, cristae cutis, brown-to-dark brown dots, and milia-like cysts, dermoscopic sign improvement was evident in both treated groups. However, fractional CO2 laser shows the superior result to retinoic acid peel in the treatment. Conclusion: Fractional CO2 laser and retinoic acid peel are considered effective modalities for neck-AN treatment. However, fractional CO2 laser was more effective.