Abstract

Acral cutaneous neural angiomatous hamartomas (ACNAHs) are benign lesions that are characterized by a disorganized proliferation of neurovascular elements. They are extremely rare with very few cases reported in the literature. We present a case of a 38-year-old male who presented to clinic with a two-year history of a growth on the right foot that was presumed to be a plantar wart refractory to over-the-counter wart therapies. Physical examination revealed a 4 mm skin colored papule on the right plantar foot proximal to the first and second digits. Regular hairpin vessels were appreciated on dermoscopy. A punch biopsy was performed and demonstrated a well circumscribed dome shaped papule with an epidermal collarette. Small neurovascular structures were scattered throughout the dermis of the papule.  Moreover, there was a lack of eccrine glands and mildly increased dermal interstitial cellularity within the lesion. Immunohistochemical stains for S100 and CD31 highlighted the nerve fibers and small vessels respectively. Considering these findings, the impression was that the lesion represented an ACNAH. There are several histopathologic similarities between ACNAH and supernummary digit, which can make distinction from one another difficult. Nevertheless, supernummary digits typically arise on the fifth digit and have prominent neural structures without admixed vessels. In contrast, our case did not arise on a digit and had prominent neural structures with accompanying vascular elements. The paucity of similar reports in the literature may reflect that these lesions are being overlooked as ACNAHs by pathologists and dermatopathologists.