Myxoid Onychomatricoma-A New Case

Area of Science:

• Dermatopathology
• Oncology

Background:

• Onychomatricoma is a rare, slow-growing benign neoplasm originating from the nail matrix.
• Histological variants exist, with
• myxoid onychomatricoma
• describing a fibromixoid subtype.

Observation:

• A 51-year-old woman presented with a year of right thumbnail thickening and discoloration, initially misdiagnosed as onychomycosis.
• Magnetic resonance imaging revealed a tumor with filamentous projections, prompting suspicion of onychomatricoma.

Findings:

• Surgical avulsion and subsequent histology confirmed a biphasic tumor with epithelial and prominent myxoid stromal components.
• Immunohistochemical staining supported the diagnosis of myxoid onychomatricoma.

Implications:

• This case represents a new instance of the rare myxoid onychomatricoma histological variant.
• Accurate diagnosis is crucial, as initial presentation can mimic common nail conditions like onychomycosis.