Age spots are not usually dangerous. The brown-colored, flat patches are technically called lentigines. (Sounds like a lentil in jeans!) Lentigines are not freckles or moles, but they are benign (not cancerous), darkly pigmented patches that typically show up as you age. They can pop up almost anywhere on your body.
The most common type, solar lentigines, are on your hands and face, and whatever skin has been exposed to lots of ultraviolet (UV) rays. The presence of solar lentigines means you probably spent too much time sunbathing (or tanning in a salon) or frolicking on the beach without sunscreen on.
While most lentigines are just a bothersome part of aging, some patches can develop a highly irregular border, darken or thicken. These spots need to be biopsied to rule out lentigo maligna melanoma, a worrisome type of lentigo. It’s a great idea to let a dermatologist take a closer look at your different skin spots and patches, just to be sure they aren’t cancerous.