Benign lentigo. Also called "age spots" or "liver spots," these flat and brown discolored patches on the skin may occur singly or in groups. They are due to an excess development of the skin pigment melanin. Lentigo spots are more common with age, and are common in people exposed to a lot of sun. They are most frequent in Caucasians, but also seen in Asian people. Lentigo is usually a harmless condition, but can occasionally turn into a slow-growing form of skin cancer.