Plexiform neurofibromas are among the most pathognomonic features of neurofibromatosis type 1 (NF1). Although characteristically benign, plexiform neurofibroma can cause pain, disfigurement and functional changes, and more importantly, it may turn malignant. We present here the case of a 3-year-old boy with progressive hemifacial hypertrophy that was colocalized with light brown-colored macules. The biopsy specimen showed that the bundles of nerve fibers were arranged in a concentric manner with myxoid changes. On the evaluation of the pigmented lesion, only the basal melanin pigments were increased in the epidermis without any melanin-laden pigmented cells in the dermis. We have demonstrated that neurofbroma needs to be considered in the differential diagnosis of
hemifacial hypertrophy since this is likely to have implications for the further management of these patients. The absence of other findings does not exclude NF1 as the underlying disease since many NF1 patients have not yet developed cafe-au-lait macules or freckles in early childhood.