We report the case of a 30-year-old female patient with non-von Recklinghausen's neurofibromatosis. In our opinion it does not fit within a system of classification recently described. Clinically, the abnormality resembled a giant pigmented nevus; however, light- and electron microscopy findings were consistent with those of a neurofibroma. No other symptoms of classic neurofibromatosis or other diseases were present. The family history showed no evidence of neurofibromatosis. To the best of our knowledge this manifestation of non-von Recklinghausen's neurofibromatosis has not been previously described. The cause and the inheritance pattern of this variant are not clear.