Superficial papular neuroma: Case series of a new entity

Background Dermal neural lesions arise in various circumstances and may be difficult to classify. Methods We describe the clinical, histopathologic and immunophenotypic features of a series of terminally differentiated neural lesions not described previously, to our knowledge. Results Four cases from men aged 58 to 66 years were included. Some lesions reportedly bled, but no inciting trauma or prior biopsies were reported. None recurred after biopsy, with follow‐up ranging from 19 to 113 months. All lesions were papular, with vertically oriented S100‐positive spindled cells and nerve fibers in the papillary dermis. Slight epidermal hyperplasia, dilated superficial thin‐walled vessels and minimal to mild inflammation were seen in each. Fibers were uniformly fine in 3 cases, with slightly thicker central fibers in the fourth. Three had parakeratotic scale. None were associated with dermal fibrosis or adnexal proliferation. Neurofilament stained axons in each. EMA was negative in all cases. CD34, melan‐A and HMB45 were negative when performed. Conclusions We report a small series of benign neural lesions and propose the name “superficial papular neuroma” for this distinct entity. Awareness is important to understand the clinical significance of these lesions and avoid misinterpretation that could lead to overtreatment, unnecessary work‐up and increased cost.