Dermoscopic features of nail unit melanoma: a scoping review

Area of Science:

• Dermatology
• Oncology
• Dermoscopy

Background:

• Nail unit melanoma (NUM) is a challenging cutaneous malignancy with often subtle clinical signs, leading to delayed diagnosis and worse prognosis.
• Dermoscopy improves early NUM detection, but literature is fragmented.
• This review synthesizes existing data to characterize NUM demographics and dermoscopic findings.

Purpose of the Study:

• To characterize demographic patterns and dermoscopic features of nail unit melanoma.
• To identify reliable dermoscopic indicators for early NUM detection and invasive disease markers.
• To highlight the need for standardized dermoscopic documentation.

Main Methods:

• A scoping review of 26 studies.
• Inclusion of 416 patients with nail unit melanoma.
• Synthesis of demographic and dermoscopic data.

Main Results:

• Adults aged 50-70 are most affected, with fingernails more common than toenails.
• Consistent dermoscopic features include heterochromia, irregular band spacing/width, and blurred borders.
• Destructive changes (nail dystrophy, ulceration) correlate with invasive NUM, while pigmentary changes suggest in situ disease.

Conclusions:

• Pigmentary irregularities are key dermoscopic indicators for NUM.
• Destructive nail changes suggest invasive NUM, prompting timely biopsy.
• Standardized dermoscopic reporting and multicenter studies are needed to improve NUM diagnosis and patient outcomes.