Cafe Au Lait spots. Which look like this: http://www.Sciencephoto.Com/media/259913/enlarge . Also, the spot must appear, that is, not be there from birth (that would be a birthmark).
Many manifestations. Commonly nf gradually appears with development of brown flat spots and soft nodules under the skin. The brown (café-au-lai) spots are the main symptom of neurofibromatosis. Freckling of armpits, neurofibromas orsubcutaneous bumps , which increase in number with age.. Lisch nodules (hamartomas of iris), gliomas of the optic nerve, skeletal dysplasias with limb abnormalities and scoliosis.