title: Cutaneous squamous cell carcinomas of the lower extremity: a distinct subset of squamous cell carcinomas.
abstract: BACKGROUND
  Some patients develop a disproportionate number of cutaneous squamous cell carcinomas (SCCs) on their lower extremity (LE).
  
  
  OBJECTIVE
  We sought to characterize the clinical features, treatment, and outcome in patients who develop multiple LE SCCs.
  
  
  METHODS
  We identified 22 patients with 4 or more biopsy-diagnosed LE SCCs during a 4.5-year study period. The location, size, treatment, and clinical outcome of each LE SCC were recorded.
  
  
  RESULTS
  Of the 22 patients studied, 18 were female. Of the 360 SCCs our patients developed, 260 (72.2%) were on the LE. The incidence of SCCs in these patients was nearly 7 times greater than the incidence of basal cell carcinoma in the same patients.
  
  
  CONCLUSIONS
  The number of patients is small and limits definitive conclusions about prevalence of SCCs on the LE in the general population.
  
  
  CONCLUSIONS
  LE SCCs are a distinct subset of cutaneous SCCs and may have distinctive clinical features and biologic behavior requiring additional study.
authors.affiliation: Department of Dermatology, Yale University, New Haven, Connecticut.
authors.forename: Changhyun
authors.initials: C
authors.lastname: Kim
authors.affiliation: Department of Dermatology, Yale University, New Haven, Connecticut; Department of Pathology, Yale University, New Haven, Connecticut.
authors.forename: Christine J
authors.initials: CJ
authors.lastname: Ko
authors.affiliation: Department of Dermatology, Yale University, New Haven, Connecticut. Electronic address: david.leffell@yale.edu.
authors.forename: David J
authors.initials: DJ
authors.lastname: Leffell
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002280:Basal Cell Carcinoma / Q000473:pathology*; D002294:Carcinoma, Squamous Cell / Q000473:pathology* / Q000601:surgery; D005260:Female; D006801:Humans; D035002:Lower Extremity / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D012878:Skin Neoplasms / Q000473:pathology* / Q000601:surgery
keywords: BCC; LE; MCS; Mohs microscopically controlled surgery; SCC; UV; basal cell carcinoma; carcinogen; epidemiology; female; immunosuppression; leg; lower extremity; squamous cell carcinoma; ultraviolet; ultraviolet radiation