title: Seborrhoeic keratosis or occult malignant neoplasm of the skin?
abstract: BACKGROUND
  Seborrhoeic keratosis is generally considered to be a benign lesion of the skin.
  
  
  METHODS
  We present the case of a 68-year-old male who presented with clinically typical seborrhoeic keratosis that later histological examination showed partially covered an occult basal cell carcinoma.
  
  
  OBJECTIVE
  To have an indication of what percentage of clinically apparent seborrhoeic keratoses may be associated with some form of histologically proven skin malignancy.
  
  
  METHODS
  We carried out a retrospective analysis of approximately 23,000 histopathological examinations done on specimens from dermatological lesions.
  
  
  RESULTS
  Fifty-nine (11.9%) clinically apparent seborrhoeic keratoses were later histologically diagnosed as basal cell carcinomas, 17 (3.4%) as squamous cell carcinomas, and five (1.01%) as malignant melanomas.
  
  
  CONCLUSIONS
  Although the association of seborrhoeic keratosis and skin malignancy appears to be relatively uncommon, the possibility of such an association cannot be ruled out.
authors.affiliation: Department of Dermatology-Venereology, University of Athens, A Sygros Hospital, Greece.
authors.forename: D
authors.initials: D
authors.lastname: Rigopoulos
authors.forename: E
authors.initials: E
authors.lastname: Rallis
authors.forename: E
authors.initials: E
authors.lastname: Toumbis-Ioannou
authors.forename: E
authors.initials: E
authors.lastname: Christophidou
authors.forename: C
authors.initials: C
authors.lastname: Limas
authors.forename: A
authors.initials: A
authors.lastname: Katsambas
mesh_terms: D000368:Aged; D001707:Biopsy, Needle; D002280:Basal Cell Carcinoma / Q000175:diagnosis / Q000473:pathology*; D046508:Culture Techniques; D003937:Diagnosis, Differential; D006801:Humans; D007150:Immunohistochemistry; D017492:Keratosis, Seborrheic / Q000175:diagnosis / Q000473:pathology*; D008297:Male; D011230:Precancerous Conditions / Q000473:pathology*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D012878:Skin Neoplasms / Q000175:diagnosis / Q000473:pathology*