Pigmented Malignant Onychopapilloma of the Fingernail: Description of the "String Sign".

ABSTRACT:

Introduction

Onychopapilloma is a benign nail tumor of the nail bed and distal matrix that typically presents as isolated longitudinal erythronychia on clinical examination. In 2021, Haneke et al. [J Cutan Pathol. 2021;48(1):174-9] described the 1st case of a malignant variant of onychopapilloma.

Case presentation

We present the case of a 34-year-old female patient, Fitzpatrick type V, who presented to our specialty outpatient nail clinic with a 10-year history of a pigmented growth on the lateral nail fold of the left 3rd fingernail that resembled a string. On histopathology, the patient's biopsy showed significant onycholemmal squamous dysplasia with intracytoplasmic melanin pigment deposition in a background of onychopapilloma; concurrent abnormal suprabasilar nuclear sta

SUBMITTER: Hill RC 

PROVIDER: S-EPMC11867635 | biostudies-literature | 2025 Jan-Dec

REPOSITORIES: biostudies-literature