Seborrhoeic keratosis

Last Updated: 2022-02-25

Author(s): Anzengruber F., Navarini A.

ICD11: 2F21.0

Verruca seborrhoica, verruca seborrhoica senilis, senile wart, seborrhoeic senile wart, seborrhoeic wart, verruca senilis, senile wart, basal cell acanthoma.

Very common, benign tumour.

  • More frequent with increasing age
  • Women = men
  • Eruptive onset in Leser-Trélat syndrome with internal neoplasia in the gastrointestinal tract or haematological disease (both anecdotal), then look for acanthosis nigricans maligna (present in 50% of Leser-Trélat syndrome patients

  • Hyperkeratotic type
  • Acanthotic type
  • Reticular/adenoid type
  • Clonal type
  • Melanoma

  • Unknown
  • Probably familial predisposition

  • Mostly localised on the trunk, partly pruritic, sharply demarcated, platelet-like, oval brownish-blackish-reddish plaques with a verrucous surface
  • Surface microscopically, the horny beads are characteristic

  • Clinical picture
  • Biopsy
    • In a few cases, the diagnosis cannot be made with certainty clinically

Exophytic, intraepidermal papillomatous proliferation of squamous cells without signs of malignancy. Horn cysts form, which are important dermatoscopically.

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