# Comparison of the Effectiveness of Fractional Carbon Dioxide Laser and Retinoic Acid Peel in the Treatment of Acanthosis Nigricans: A Randomized Controlled Trial

## TL;DR

This study compares fractional CO2 laser and retinoic acid peel for treating Acanthosis Nigricans and finds the laser to be more effective with fewer side effects.

## Contribution

The study provides a direct comparison of two treatment modalities for Acanthosis Nigricans using a randomized controlled trial.

## Key findings

- Fractional CO2 laser showed a greater reduction in ANASI scores compared to retinoic acid peel.
- Laser treatment required fewer sessions and had minimal side effects.
- Results from the laser were more sustainable in the long term.

## Abstract

Introduction

Acanthosis nigricans (AN) is a common skin disorder with varied aetiology and a wide palette of treatment options. Despite multiple options available for management, laser as a modality has recently evolved and shown better outcomes. Some fractional ablative lasers induce a very narrow tissue column of thermal damage and neocollagenesis, thereby improving textural irregularities, whereas retinoids, a first-line drug, help in superficial skin peeling. The study was conducted to determine the efficacy of fractional carbon dioxide (CO2) laser and retinoic acid peel and to decide which is a better and safer treatment option to address AN.

Methods

This is a prospective randomised controlled trial. A total of 38 patients were included in this study and divided into two equal groups. Group A was treated with fractional CO2 laser(n=19) and group B was treated with retinoic acid peel (n=19) using the sequentially numbered, opaque, sealed envelope (SNOSE) technique via allocation concealment method and a computer-generated random number table. Group A received four sessions of laser treatment at two-week intervals, and group B received four sessions of peel treatment at three-week intervals. Both groups were analysed using the acanthosis nigricans area and severity index (ANASI), dermoscopy, and two blinded dermatologists before and one month after the treatment. MedCalc software version 19.0.5 (MedCalc Software, Ostend, BEL) was used for statistical analysis.

Results and conclusion

There was a high statistically significant difference noted in the mean ANASI score in both groups. The fall in ANASI score that denoted the treatment response was greater in group A compared to group B, signifying superior results of fractional CO2 laser compared to retinoid acid peel. The Fractional CO2 laser was more efficacious than retinoic acid peel in the management of AN with sustainable results in the long term, minimal side effects, and required fewer sessions.