title: Combined 5-fluorouracil and Er:YAG laser treatment in a case of recurrent giant keratoacanthoma of the lower leg.
abstract: BACKGROUND
  Keratoacanthomas are fast-growing squamous tumors, which usually show spontaneous regression. The development of giant variants with an aggressive behavior has been described. Although surgical excision remains the treatment of choice for very large keratoacanthomas, other therapeutic options including laser surgery and topical chemotherapy may be superior in special situations.
  
  
  OBJECTIVE
  The objective was to evaluate the efficacy of Er:YAG laser surgery combined with topical 5-fluorouracil treatment in a case of recurrent giant keratoacanthoma.
  
  
  METHODS
  A 64-year-old woman presented for evaluation and treatment of recurrent tumors in her face and extremities. Despite repeated invasive surgical removal of these lesions, recurrence of fast-growing giant keratoacanthomas developed in the pretibial region of her left lower leg. Owing to recurrence after conventional surgery and the tumor size, a novel treatment method using ablative Er:YAG laser combined with topical 5-fluorouracil was performed.
  
  
  RESULTS
  After four treatments with excellent patient compliance, histologic analysis of punch biopsies revealed tumor-free ulcerations. Complete epithelization was obtained after 9 weeks. Six months after the treatment, no recurrence was observed.
  
  
  CONCLUSIONS
  The combined use of ablative Er:YAG laser and topical 5-fluorouracil chemotherapy may be considered as an effective treatment option in cases of giant keratoacanthoma when conventional surgery is not indicated.
authors.affiliation: Department of Dermatology, Friedrich-Schiller-University of Jena, Jena, Germany. j-thiele@northwestern.edu
authors.forename: Jens J
authors.initials: JJ
authors.lastname: Thiele
authors.forename: Mirjana
authors.initials: M
authors.lastname: Ziemer
authors.forename: Silke
authors.initials: S
authors.lastname: Fuchs
authors.forename: Peter
authors.initials: P
authors.lastname: Elsner
mesh_terms: D000279:Administration, Cutaneous; D000964:Antimetabolites, Antineoplastic / Q000008:administration & dosage / Q000627:therapeutic use*; D003131:Combined Modality Therapy; D003937:Diagnosis, Differential; D004334:Drug Administration Schedule; D005260:Female; D005472:Fluorouracil / Q000008:administration & dosage / Q000627:therapeutic use*; D006801:Humans; D007636:Keratoacanthoma / Q000175:diagnosis* / Q000188:drug therapy / Q000473:pathology / Q000601:surgery; D053685:Laser Therapy; D007866:Leg; D008875:Middle Aged; D012008:Recurrence; D012871:Skin Diseases / Q000175:diagnosis* / Q000188:drug therapy / Q000473:pathology / Q000601:surgery
chemical_list: D000964:Antimetabolites, Antineoplastic; D005472:Fluorouracil