Nail matrix melanoma in adolescents and young adults: a retrospective dermoscopic study.
42% of nail matrix melanoma cases occurred in patients aged 40 or younger
Nail matrix melanoma in adolescents and young adults: a retrospective dermoscopic study.
Nail matrix melanoma (nail matrix melanoma) is a rare subtype of melanoma, accounting for approximately 2-3% of all melanoma cases.
To characterize the clinical, dermoscopic and histopathological features of nail matrix melanoma in patients aged 40 years or younger and to raise awareness about the occurrence of melanoma in this rarely affected age group.
We retrospectively reviewed all histopathologically confirmed cases of nail matrix melanoma diagnosed at our institution between 2015 and 2025.
42% of cases arose in patients 40 or younger, not just older adults
Among the ≤ 40-year age group, 22 (88%) had melanoma in situ and 3 (12%) had invasive melanoma, with a mean Breslow thickness of 1.0 (range 0.7-1.4) mm.
Dermoscopy revealed irregular longitudinal lines in 96%, three or more colours in 65%, and disruption of parallelism in 74% of lesions.
Spiral melanonychia, a pattern commonly linked to benign naevi, was observed in 26% of cases.
Comparative analysis with 64 age-matched patients with nonacral, nonmucosal cutaneous melanomas showed a higher proportion of in situ disease among patients with nail matrix melanoma.
Nail matrix melanoma can also occur in adolescents and young adults - an age group in which it is often under-recognized. Despite most cases being diagnosed at an early (in situ) stage, delays in diagnosis are common.
Clinicians should maintain a high index of suspicion for solitary, atypical longitudinal melanonychia developing after puberty to improve diagnostic accuracy and patient outcomes.