title: Studying regression of seborrheic keratosis in lichenoid keratosis with sequential dermoscopy imaging.
abstract: BACKGROUND
  Lichenoid keratosis (LK) is a well-described entity that has been proposed to represent a regressive response to a pre-existent epidermal lesion.
  
  
  OBJECTIVE
  To evaluate the natural evolution of a series of cases showing the intermediate stage of the regression of seborrheic keratosis in LK using sequential dermoscopy imaging over time.
  
  
  METHODS
  A series of lesions with dermoscopic areas of seborrheic keratosis and LK in the same tumor were consecutively collected for over 3 years at the Dermatology Department of the Hospital de Sant Pau i Santa Tecla, Tarragona, Spain. Sequential dermoscopic images of each case were collected quarterly for 1 year. At the end of the follow-up, all the lesions were biopsied.
  
  
  RESULTS
  A total of 22 cases were collected. At the end of the follow-up, the LK part increased in all the lesions. In 11 cases (50%), the seborrheic keratosis part disappeared completely, and in another 5 cases (22.7%), seborrheic keratosis comprised only 10% of the remaining area.
  
  
  CONCLUSIONS
  These dermoscopic study findings support the proposal that LK represents a regressive response to a pre-existent epidermal lesion, in this case seborrheic keratosis.
authors.affiliation: Department of Dermatology, Hospital de Sant Pau i Santa Tecla, Tarragona, Spain. pzaballos@aedv.es
authors.forename: Pedro
authors.initials: P
authors.lastname: Zaballos
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Salsench
authors.forename: Patricia
authors.initials: P
authors.lastname: Serrano
authors.forename: Francisco
authors.initials: F
authors.lastname: Cuellar
authors.forename: Susana
authors.initials: S
authors.lastname: Puig
authors.forename: Josep
authors.initials: J
authors.lastname: Malvehy
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D046169:Dermoscopy; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D017492:Keratosis, Seborrheic / Q000175:diagnosis* / Q000473:pathology; D008010:Lichen Planus / Q000175:diagnosis* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D012878:Skin Neoplasms / Q000175:diagnosis / Q000473:pathology; D012880:Skin Pigmentation