Factors Related to Nevus-Associated Cutaneous Melanoma: A Case-Case Study

Abstract

A proportion of cutaneous melanomas display neval remnants on histologic examination. Converging lines of epidemiologic and molecular evidence suggest that melanomas arising from nevus precursors differ from melanomas arising de novo. In a large, population-based study comprising 636 cutaneous melanomas subjected to dermatopathology review, we explored the molecular, host, and environmental factors associated with the presence of neval remnants. We found that nevus-associated melanomas were significantly associated with younger age at presentation, non-brown eye color, trunk site, thickness of less than 0.5 mm, and BRAF mutation. Compared with patients with de novo melanomas, those with nevus-associated tumors were more likely to self-report many moles on their skin as a teenager (odds ratio = 1.94, 95% confidence interval = 1.01-3.72) but less likely to report many facial freckles (odds ratio = 0.49, 95% confidence interval = 0.25-0.96). They also had high total nevus counts (odds ratio = 2.18, 95% confidence interval = 1.26-3.78). On histologic examination, nevus-associated melanomas exhibited less dermal elastosis in adjacent skin compared with de novo melanomas (odds ratio = 0.55, 95% confidence interval = 0.30-1.01). These epidemiologic data accord with the emerging molecular paradigm that nevus-associated melanomas arise through a distinct sequence of causal events that differ from those leading to other cutaneous melanomas.

Nevus‐associated melanoma: An observational retrospective study of 22 patients evaluated with dermoscopy and reflectance confocal microscopy

“…NAM usually appears in younger patients than de novo melanoma (DNM), with multiple nevi and in intermittently sun‐exposed skin areas as the trunk or extremities, as it occurs in our work. According to some authors, personal history of NAM is the most important risk factor to have another NAM, so this group of patients may benefit even more of digital dermoscopic follow‐up.…”

“…The most frequent histologic subtype of NAM is superficial spreading melanoma, as well as in our series. Some works point out that NAM usually has lower Breslow depth, stage and the biopsy of sentinel lymph node is more often negative . However, this data should be interpreted with caution, as thicker NAM could mask the nevus remnants as it grows involving them and therefore being misdiagnosed as DNM.…”

Nevus Count Associations with Thinner Nodular or Superficial Spreading Melanoma

“…It included 16,180 cases and reported similar nevi counts associated with melanoma of each histological subtype, without heterogeneity among RRs: 1.31 and 1.32 for NM and SSM, respectively (although NM was not directly compared to SSM) (7). Interestingly, higher nevus counts have been associated with thinner melanoma (8,9), better survival rates independently of Breslow thickness (8) and, more recently, with melanoma associated histologically with a nevus (10). A previous age-stratified study reported that for individuals younger than 60 years, the presence of more than 50 total nevi was associated with thinner melanoma, although the histological subtype was not investigated (9).…”

‘Mind your Moles’ study: protocol of a prospective cohort study of melanocytic naevi

“…In both adults and children, new naevi can develop and existing naevi can regress. 5–7 Melanomas often grow adjacent to, or in some cases, within pre-existing naevi 8 and naevi are the major differential diagnosis of primary melanoma. 9 Therefore, improved understanding of naevus development and recognition of the importance of changes over time is key to understanding melanoma development and will help establish more efficient prevention and early detection models for melanoma.…”