Café-Au-Lait is French for coffee with milk. So basically this is what they look like: flat, light tan to brown flat spots. Their sizes are very variable, from 2cm to 20 cm in diameter. Up to 13% of the population has one or more of these spots. They may appear at birth or soon after and increase in numbers in subsequent years.

These spots are caused by an increase in melanin content with the presence of giant melanosomes.

To have a few such spots is totally normal. However, if there are 6 or more Café-Au-Lait spots in children or adults, and they are at least 15 mm in diameter in patients older than 5 years or over 5 mm in children younger than 5 years, it could be the sign of a disease known as neurofibromatosis, an inherited autosomal dominant disorder. This disorder can be highly variable in its expression, with members in the same family showing differing degrees of severity. Other features are required to make this diagnosis and some people may have multiple spots without having the disease.

The response to laser can be very variable. Sometimes 2 treatments can remove the spots completely, while other cases may need 5 or 6 treatments.