title: Keratoacanthoma with perineural invasion: an indicator for aggressive behavior?
abstract: Neurotropic invasion of keratoacanthoma (KA) is rare and can easily be missed histologically. A 36-year-old woman developed a KA on the upper lip four weeks after CO(2) laser skin resurfacing; it showed microscopic evidence of perineural invasion. Despite repeated treatment with intralesional methotrexate, the KA recurred after 6 months. She was then treated with ionizing radiation (56 Gy) and has been tumor-free for more than 3 years. Immunohistochemistry showed decreased expression of desmoglein 1 as it is seen in squamous cell carcinomas. In most cases not much importance is attached to perineural invasion which is frequently seen in KA because of the high rate of spontaneous regression. Our case suggests that perineural invasion may be an indicator for aggressive growth of head-and-neck KAs so that histologically-controlled excision is recommended.
authors.affiliation: Department of Dermatology, University of Münster, Münster, Germany.
authors.forename: Yasmin
authors.initials: Y
authors.lastname: Basoglu
authors.forename: Dieter
authors.initials: D
authors.lastname: Metze
authors.forename: Dorothee
authors.initials: D
authors.lastname: Nashan
authors.forename: Sonja
authors.initials: S
authors.lastname: Ständer
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007636:Keratoacanthoma / Q000473:pathology* / Q000628:therapy*; D008048:Lip Neoplasms / Q000473:pathology* / Q000628:therapy*; D009361:Neoplasm Invasiveness; D010524:Peripheral Nervous System Neoplasms / Q000473:pathology* / Q000628:therapy*; D016896:Treatment Outcome