Cutaneous Solitary Neural Hamartoma: Report of an Unusual Case

Abstract

Cutaneous hamartomas are tumor-like proliferations of tissue indigenous to the organ but arranged abnormally. There are examples in the literature of cutaneous hamartomas composed of a variety of different components. To our knowledge, there is no previous report of such cutaneous solitary neural hamartoma. Our case occurred in a 51-year-old man with pain and paresthesia in the right shoulder associated with a nodule that was surgically removed. There was no history of trauma, other skin nodules, neurofibromatosis, or tuberous sclerosis. Histologically, there was an unencapsulated nodule, composed of mature nerve bundles noted abnormally high within the papillary dermis, extending to the reticular dermis with periadnexal distribution. Immunohistochemically, the nerve bundles were positive for S-100, including the smaller nerve twigs, and the perineurium was highlighted by epithelial membrane antigen, reminiscent of normal peripheral nerves. Although, neural components including mature nerve bundles have been described in various cutaneous hamartomas, this represents a peculiar case of a cutaneous mature peripheral nerve hamartoma. Whether this is related to other entities of cutaneous hamartomas (ie, neurofollicular hamartoma, folliculosebaceous cystic hamartoma) is not yet apparent, although it is probably a unique entity.

Superficial papular neuroma: Case series of a new entity

“…Cutaneous solitary neural hamartoma is described as an unencapsulated nodule of haphazardly arranged, thick nerve fascicles in a periadnexal distribution, within the papillary and reticular dermis. These thick nerve bundles are S100 positive, contain neurofilament‐positive axons and are surrounded by EMA‐positive perineurium . Unlike the nerve fascicles in cutaneous solitary neural hamartoma, the fibers in our series were smaller, vertically oriented, mostly confined to the papillary dermis and lacked a periadnexal distribution.…”

“…Although most dermal lesions with neural differentiation are classifiable using well‐established diagnoses, some are not. As a consequence, several new entities have been reported in the last decade …”

Oral neurovascular hamartoma: an extraordinary verdict in the oral cavity

“…Prior to that, Goldsmith et al 6 described a case of leiomyomatous hamartoma of the posterior tongue leading to dysphagia in a 16-year-old, whereas Miyamoto et al 7 documented a lingual hamartoma in a child with a cleft palate. Al Habeeb et al 8 reported a solitary but cutaneous neural hamartoma in a middle-aged individual. The lesion had histological characteristics comprising of numerous mature nerve bundles within the papillary dermis.…”

Acral Cutaneous Neural Angiomatous Hamartoma: A Variant of Palmar Cutaneous Hamartoma?

“…Al Habeeb et al have described a case of cutaneous solitary neural hamartoma in a 51-year-old man [1]. This right shoulder unencapsulated lesion was composed of mature nerve bundles abnormally high within the papillary dermis, extending into the reticular dermis with a periadnexal distribution.…”