Morphological features of naevoid melanoma: results of a multicentre study of the International Dermoscopy Society

Br J Dermatol. 2015 Apr;172(4):961-7. doi: 10.1111/bjd.13524. Epub 2015 Mar 5.


Background: Naevoid melanoma (NeM), a rare variant of melanoma, can be difficult to detect as its clinical and histopathological morphology can simulate a naevus.

Objectives: To describe the clinical and dermoscopic features associated with NeM.

Methods: Lesions with a histopathological diagnosis of NeM were collected via an e-mail request sent to all members of the International Dermoscopy Society. All lesions were histopathologically reviewed and only lesions fulfilling a set of predefined histopathological criteria were included in the study and analysed for their clinical and dermoscopic features.

Results: Twenty-seven of 58 cases (47%) fulfilled the predefined histopathological criteria for NeM and were included in the study. Clinically, 16 of the 27 NeMs presented as a nodular lesion (59%), eight (30%) as plaque type and three (11%) as papular. Analysis of the global dermoscopic pattern identified three types of NeM. The first were naevus-like tumours (n = 13, 48%), typified by a papillomatous surface resembling a dermal naevus. In these lesions local dermoscopic features included irregular dots/globules (46%), multiple milia-like cysts (38%) and atypical vascular structures (46%). The second type were amelanotic tumours (n = 8, 30%), typified by an atypical vascular pattern (75%). The third type consisted of tumours displaying a multicomponent pattern (n = 4, 15%), characterized by classical local melanoma-specific criteria. Two lesions (7%) were classified as mixed-pattern tumours as they did not manifest any of the aforementioned patterns.

Conclusions: While NeMs may be clinically difficult to differentiate from naevi, any papillomatous lesion displaying dermoscopically atypical vessels and/or irregular dots/globules should prompt consideration for the possible diagnosis of NeM.

Publication types

  • Clinical Study
  • Multicenter Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Dermoscopy
  • Diagnosis, Differential
  • Female
  • Humans
  • Male
  • Middle Aged
  • Nevus, Pigmented / pathology*
  • Skin Neoplasms / pathology*