​Dermatology - Blue Nevus

​Dermatology - Blue Nevus
A blue nevus is a skin lesion that is acquired and characterized by a solid, dark-blue to gray-to-black, well-defined raised area or lump. It is caused by the localized growth of melanin-producing cells called dermal melanocytes.
There exist three categories: common, mixed, and cellular. The common and combination forms are considered innocuous. Cellular blue nevi exhibit a bigger size and have a very low likelihood of developing into a malignant state.
Abnormalities
The typical forms of this condition are papules or nodules, which have a blue-gray or blue-black color and are smaller than 10 mm in diameter. Cellular blue nevi have a bigger size, exceeding 1 centimeter, and display an uneven shape.
The diagnosis is based on clinical assessment and can be verified with a biopsy. The differential diagnosis include dermatofibroma, glomus tumor, nodular or metastatic melanoma, traumatic tattoo, and pigmented basal cell cancer.

Treatment is unnecessary for common or mixed nevi. Surgical removal is recommended for cellular blue nevi.