Acanthosis nigricans (pronounced: ah-kan-THO-sis NY-gruh-kans) is a skin disorder that results in velvety, light-brown-to-black patches or marks that occur in areas of your skin that has folds, ...

In acanthosis nigricans, the skin becomes thick and velvety. It may appear gray, brown, or black, and often appears in skin folds. It is often a sign of an underlying condition, such as insulin ...

Acanthosis nigricans involves dark, velvety patches of skin, often appearing in skin folds, and can sometimes be itchy or odorous. The primary cause is often high insulin levels, frequently linked to ...