Solar lentigo is a circumscribed 1- to 3-cm brown macule resulting from a localized proliferation of melanocytes due to acute or chronic exposure to sunlight. Age of Onset Usually 40 years but may be 30 years in sunny climates and in susceptible persons. Race Most common in Caucasians but seen also in Asians. Multiple dark-brown macules on the forehead occurred after a sunburn. They are all of about the same size and sharply marginated that is characteristic of sunburninduced solar lentigines.