Clinical and dermoscopic characteristics of congenital and noncongenital nevus-associated melanomas

J Am Acad Dermatol. 2020 Oct;83(4):1080-1087. doi: 10.1016/j.jaad.2020.04.120. Epub 2020 Apr 28.

Abstract

Background: No specific features of nevus-associated melanoma (NAM) are currently defined.

Objective: To identify clinical/dermoscopic features of NAM.

Methods: Retrospective evaluation of histopathologically diagnosed NAM.

Results: Eighty of 165 NAMs had a clinically recognizable nevus component, often raised or nodular, most frequently characterized by different morphologic clones and/or colors. In 111 of 165 NAMs, dermoscopy showed a nevus component, prevalently characterized by regular dots/clods and structureless brown areas. Clinically, the melanoma component was eccentric/peripheral in 45 of 80 cases and central in 35 of 80; dermoscopically, the figures were 59 of 111 and 52 of 111, respectively. Melanomas associated with congenital nevi (C-NAMs) occur at a younger age and have a thicker Breslow depth than melanomas associated with acquired nevi (NC-NAMs). Dermoscopically, regular dots/globules characterize C-NAMs, and hypopigmented structureless areas characterize NC-NAMs.

Limitations: Retrospective analysis.

Conclusion: C-NAMs are more often central to a congenital nevus, with a clod/globular or structureless brown pattern, typical of young patients. NC-NAMs are frequently hypopigmented nodules/plaques, eccentric/peripheral, with hypopigmented structureless areas, typical of older patients.

Keywords: dermoscopy; melanoma; nevogenesis; nevus; nevus-associated melanoma; skin cancer.

MeSH terms

  • Adolescent
  • Adult
  • Age of Onset
  • Aged
  • Aged, 80 and over
  • Austria / epidemiology
  • Cell Transformation, Neoplastic
  • Child
  • Dermoscopy
  • Disease Progression
  • Female
  • Humans
  • Italy / epidemiology
  • Male
  • Melanoma / congenital
  • Melanoma / epidemiology
  • Melanoma / pathology*
  • Middle Aged
  • Models, Biological
  • Nevus, Pigmented / congenital
  • Nevus, Pigmented / epidemiology
  • Nevus, Pigmented / pathology*
  • Organ Specificity
  • Retrospective Studies
  • Skin Neoplasms / congenital
  • Skin Neoplasms / epidemiology
  • Skin Neoplasms / pathology*
  • Young Adult