The first manifestation to appear in neurofibromatosis 1 (NF1) is pigmented macular lesions called café-au-lait spots, especially in unexposed areas of skin such as axilla (axillary freckle sign). Solitary lesions are common in normal individuals. They are considered significant for NF1 only when there are 6 or more lesions measuring >5 mm in diameter in prepubertal individuals or >15 mm in diameter in postpubertal individuals. Café-au-lait spots become larger and darker with age and are somewhat correlated with the severity of the disease. Microscopically, they show increased amounts of melanin in the basal cell layer of epidermis. The image shows an 8 cm size cafe-au-lait spot in a patient with NF1. The patient had multiple café-au-lait spots on back and hip, multiple neurofibromas all over body and bilateral optic nerve gliomas (pilocytic astrocytomas). There was positive family history as well (father, grandfather, and brothers). Image copyright: pathorama.ch.