# Dermoscopy of Onychopapilloma: A Benign Mimic of Subungual Malignancy

## TL;DR

Onychopapilloma is a benign nail condition that can look like cancer, but can often be diagnosed without a biopsy using dermoscopy.

## Contribution

The paper highlights the use of dermoscopy to distinguish onychopapilloma from subungual malignancies.

## Key findings

- Dermoscopy showed splinter hemorrhages and subungual hyperkeratosis in a stable, asymptomatic lesion.
- Onychopapilloma can be differentiated from malignant conditions using clinical and dermoscopic features.
- Biopsy is unnecessary for stable, asymptomatic cases but recommended if changes occur.

## Abstract

Onychopapilloma is a benign tumor of the nail bed and distal matrix, commonly presenting with longitudinal erythronychia and distal subungual hyperkeratosis. A 30-year-old Asian male presented with an asymptomatic, stable discoloration of the thumbnail, with longitudinal erythronychia, distal onycholysis, and V-shaped fissuring. Dermoscopy revealed splinter hemorrhages and focal distal subungual hyperkeratosis beneath the V-shaped notch. The lesion was unchanging over several years, and the patient opted for conservative management with periodic monitoring rather than biopsy. Based on clinical and dermoscopic features, onychopapilloma can often be distinguished from malignant conditions such as amelanotic melanoma and squamous cell carcinoma. Differential diagnoses include glomus tumor, trauma, Darier disease, and lichen planus. While biopsy is not needed for stable, asymptomatic cases, it is recommended if the lesion changes or becomes symptomatic.