Carcinoma in situ of skin, also known as Bowen's disease, is a type of skin cancer that affects the top layer of the skin. Unlike other forms of skin cancer, carcinoma in situ does not spread to other parts of the body, but it can become invasive if left untreated. It typically appears as a red, scaly patch on the skin that doesn't heal.
If you notice a red, scaly patch on your skin that doesn't heal, it is important to see a dermatologist for a diagnosis. Early detection and treatment of carcinoma in situ of skin can prevent it from becoming invasive and spreading to other parts of the body.