Melanocytic nevus (mole) is a benign cutaneous tumor composed of pigment-producing nevus cells derived from melanocytes.
Histopathology: well-nested melanocytic proliferations at the dermal-epidermal junction
Common acquired melanocytic nevus
Definition: an acquired melanocytic nevus that arises from clusters of melanocytic nevus cells in the epidermis and dermis and manifests as a uniformly pigmented lesion
Epidemiology: common regardless of age, gender, or ethnicity
Clinical features
Most commonly on sun-exposed areas
Uniform in color and shape
Stages
Junctional nevus
Uniformly brown-black macule with a flat smooth, hairless surface and well-demarcated border
Grows at the dermal-epidermal junction during childhood
Compound nevus
Uniformly brown-black, dome-shaped elevated papule or nodule with a smooth or verrucous surface; hair may be present
Arises from a junctional nevus and extends to the dermis after childhood
Dermal nevus
Uniformly brown-black, dome-shaped elevated nodule with a smooth or verrucous surface; can become fibrotic over time and hair may be present
Arises from a compound nevus in the dermis in adults
