Blue nevus

Blue nevus
Micrograph of a blue nevus showing the characteristic pigmented melanocytes between bundles of collagen. H&E stain.
Classification and external resources
Specialty	oncology, dermatology
ICD-10	D22 (ILDS D22.L42)
DiseasesDB	31098
MeSH	D018329
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Blue nevus (also known as "blue neuronevus," "dermal melanocytoma," and "nevus bleu") is a type of melanocytic nevus. The blue colour is caused by the pigment being deeper in the skin than in ordinary nevi. In principle they are harmless but they can sometimes be mimicked by malignant lesions, i.e. some melanomas can look like a blue nevus.

Blue nevi may be divided into the following types:

Cellular blue nevus

Nevus coeruleus

Epithelioid blue nevus

Malignant blue nevus

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