Seborrheic keratosis can be seen on those who are in 20s and almost all the elderly people have at least one. It tends to occur on the sun-damaged skin. A brown spot gradually elevates to form a nodule in a long run. It is a benign lesion. A dermoscope is a device to examine a skin lesion with strong light and is used to make a clinical diagnosis.

The management includes cryotherapy which causes the lesion a burn injury with liquid nitrogen and a surgery.