What is the Blue Nevus

The Blue Nevus
Onset: appears in childhood.
Site: most common on the extremities, head and neck, buttock and dorsum of the hands.
Size: usually less than 0.5 cm.
Appearance: a solitary, slightly elevated, round, regular nevus. A rare variant, the cellular blue nevus, is larger (usually greater than 1 cm) and nodular and is frequently located on the buttock.
Color: Blueish coloration is attributed to intensely pigmented melanocytes located in the mid to lower dermis. The brown pigment absorbs the longer wavelengths of light and scatters blue light. This is called the Tyndall effect.
Progression: Melanomas are reported arising in association with a common or cellular blue nevus and arising de novo and resembling cellular blue nevi.
Treatment: may be removed for cosmetic purposes.



Intensely pigmented melanocytes located in the mid to lower dermis




The cellular blue nevus




Progression to Melanoma