Acanthosis nigricans

Overview

Acanthosis nigricans typically occurs in people who are obese or have diabetes. More rarely, it can be a warning sign of a cancerous tumor in an internal organ, such as the stomach or liver.

Symptoms

It often affects the armpits, groin, and neck. The affected skin can thicken and may smell bad.

Treatments

Treating underlying conditions, such as obesity or a tumor, may restore the skin.