A skin disorder in which dark brown or gray velvety plaques appear on the skin, typically under the arms, in the groin or upper thighs, on the neck, or near the genitalia.
They usually appear in patients with relative insulin excess, such as adults with obesity, type 2 diabetes mellitus, or polycystic ovaries. The condition may rarely be associated with internal malignancy.
SYN: keratosis nigricans

Main entry:
acanthosis