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Hundreds of cutaneous neurofibromas associated with neurofibromatosis!!

Neurofibromatosis type 1 is characterized by changes in skin coloring (pigmentation) and the growth of benign tumors along nerves in the skin, brain, and other parts of the body. Cutaneous neurofibromas are benign nerve sheath tumors composed of cells of neuromesenchymal origin, including Schwann cells, fibroblasts, perineurial cells, and mast cells. Multiple cutaneous neurofibromas and their variants (ie, plexiform, dermal) may occur in the setting of neurofibromatosis. These are benign and do not carry an increased risk of malignant transformation, but they often represent a major cosmetic problem. Many have also multiple café-au-lait spots, which are flat patches on the skin that are darker than the surrounding area. NF-1 is caused by a mutation of a gene on the long arm of chromosome 17 which encodes a protein known as neurofibromin, which is a negative regulator of the Ras oncogene signal transduction pathway. When Ras isn’t regulated, it is overexpressed. These are a family of proteins that are involved in cellular signal transduction. A cascade effect occurs when ras is “switched on” by incoming signals, leading to activation of other proteins, which, in turn, activate genes responsible for cell growth and differentiation, hence leading to neurofibromas. Due to their benign nature, neurofibromas should be surgically excised only when symptomatic.