Elderly warts are medically known as seborrheic keratosis, and the difference between seborrheic keratosis and flat warts is mainly the difference in cause, symptoms, and treatment. 1. Causes: flat warts are abnormal epidermal hyperplasia caused by HPV virus infection when the body’s immune function decreases, mostly appearing suddenly. Seborrheic keratosis is a benign intra-epidermal tumor caused by delayed development of keratin-forming cells. It is generally associated with sun exposure, heredity and other factors. 2. Symptoms: flat warts is a kind of flat papules of different sizes, the surface is mildly elevated, smooth and rounded, the boundary is clear, infectious and itchy. It can be arranged in a linear fashion because of localized scratching. Seborrheic keratosis is initially a light brown patch with clear boundaries and a scattered distribution, and with the gradual increase of skin damage, the epidermis will appear hyperplasia, roughness, deepening of the color patch, and there is usually no itching. 3. Treatment: flat warts can be treated with topical medication such as imiquimod ointment, salicylic acid ointment, etc., and if the symptoms are more serious, laser treatment can be taken. Seborrheic keratosis generally does not need treatment, if there is an aesthetic need, you can follow the doctor’s instructions to use laser, freezing and other ways of treatment. If you have seborrheic keratosis or flat warts, please go to the hospital according to the situation, don’t treat it by yourself, and follow the doctor’s instructions to use medication.