Reexcision Perineural Invasion and Epithelial Sheath Neuroma Possibly on a Spectrum of Postinjury Reactive Hyperplasia Mediated by IL-6.

TitleReexcision Perineural Invasion and Epithelial Sheath Neuroma Possibly on a Spectrum of Postinjury Reactive Hyperplasia Mediated by IL-6.
Publication TypeJournal Article
Year of Publication2017
AuthorsWang JY, Nuovo G, Kline M, Magro CM
JournalAm J Dermatopathol
Volume39
Issue1
Pagination49-52
Date Published2017 Jan
ISSN1533-0311
KeywordsAdult, Aged, Aged, 80 and over, Back, Biomarkers, Tumor, Biopsy, Cicatrix, Dysplastic Nevus Syndrome, Epithelial Cells, Female, Fluorescent Antibody Technique, Humans, Hyperplasia, Interleukin-6, Keratins, Male, Middle Aged, Neoplasm Invasiveness, Neuroma, Peripheral Nerves, Skin Neoplasms, Up-Regulation
Abstract

Epithelial sheath neuroma is a rarely recognized but established entity in the medical literature. First described in 2000 by Requena et al, there have only been 7 published cases to date, mostly in female patients and presenting as symptomatic solitary lesions on the back without a known history of trauma. In 2006, Beer et al described and reviewed a dozen cases in which epithelial sheath neuroma-like features were seen in the advent of a surgical procedure, which was termed "re-excision perineural invasion" and attributed to possible eccrine duct implantation during surgery. Our case is a 66-year-old male patient who underwent an excision of a melanocytic neoplasm in which a reactive epithelial sheath neuroma was incidentally discovered in the excision specimen, adjacent to the biopsy site cicatrix. Histologically, there was benign cutaneous nerve hyperplasia with a proliferation of squamous epithelium in intimate apposition to the nerve bundles in the superficial dermis. We postulate that the process active in the formation of re-excision perineural invasion is the same as in epithelial sheath neuroma and that minor trauma not appreciable on histologic examination is responsible in the latter entity. We performed IL-6 staining and documented that IL-6 was upregulated at the interface of the nerve and reactive epithelium, but was absent in nerves distant from the site of surgery, suggesting that IL-6 may be essential to the lesion's development. The recognition of reactive epithelial sheath neuroma including the subcategory of re-excision perineural invasion is crucial for the dermatopathologist to prevent mislabeling this reactive entity as a perineural squamous cell carcinoma, which has clinical consequences for the patient such as wider re-excision and radiation treatment. Additionally, we have identified a potential pathophysiologic basis for this lesion.

DOI10.1097/DAD.0000000000000671
Alternate JournalAm J Dermatopathol
PubMed ID27749287
Related Faculty: 
Cynthia M. Magro, M.D.

Pathology & Laboratory Medicine 1300 York Avenue New York, NY 10065 Phone: (212) 746-6464
Surgical Pathology: (212) 746-2700