title: Tattoo-associated keratoacanthomas: a series of 8 patients with 11 keratoacanthomas.
abstract: BACKGROUND
  Keratoacanthoma is interpreted by many dermatopathologists in the United States as a form of squamous cell carcinoma that can spontaneously involute. Rare examples arising in tattoos have been reported in the literature.
  
  
  METHODS
  We retrospectively reviewed all cases from our institution received between 2000 and 2008 for any that reported a tumor within a tattoo.
  
  
  RESULTS
  We identified eight patients with keratoacanthomas that arose within tattoos. One of the patients had four separate keratoacanthomas arising within two separate tattoos. Red tattoo ink was associated with 82% of the keratoacanthomas.
  
  
  CONCLUSIONS
  Keratoacanthomas are more common than previously reported in tattoos and are easily misinterpreted. The association with red tattoo ink suggests a form of hypersensitivity-associated with adnexal hyperplasia. Tattoo-associated squamous tumors with innocuous nuclei, infundibulocystic structures, adnexal hyperplasia, and signs of regression should be reported as keratoacanthomas rather than as variants of squamous cell carcinoma.
authors.affiliation: Kansas University Medial Center, Department of Pathology, 3901 Rainbow Boulevard, Kansas City, KS 66160, USA. garth.fraga@mawdpathology.com
authors.forename: Garth R
authors.initials: GR
authors.lastname: Fraga
authors.forename: Trisha A
authors.initials: TA
authors.lastname: Prossick
mesh_terms: D000328:Adult; D000368:Aged; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007636:Keratoacanthoma / Q000175:diagnosis* / Q000209:etiology; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012871:Skin Diseases / Q000175:diagnosis* / Q000209:etiology; D013653:Tattooing / Q000009:adverse effects*