False "melanocytic" parameters shown by pigmented seborrheic keratoses: a finding which is not uncommon in dermoscopy

Dermatol Surg. 2002 Aug;28(8):776-9. doi: 10.1046/j.1524-4725.2002.02002.x.

Abstract

Background: Dermoscopic evaluation of pigmented lesions includes assessment of criteria suggestive of melanocytic proliferation. Dermoscopic diagnosis may be hampered when a nonmelanocytic lesion displays one or more melanocytic features.

Objective: To evaluate the incidence of misleading dermoscopic features characteristic of melanocytic lesions in pigmented seborrheic keratosis (PSK).

Methods: We evaluated 402 clinically typical PSKs from 138 patients with at least one clinically identifiable PSK.

Results: Approximately 10% of PSKs displayed one or more melanocytic features, the most frequent being a "false" pigment network.

Conclusion: The occurrence of a "false" pigment network in PSK can be misleading in the differential diagnosis of clinically equivocal lesions. A correct diagnosis can only be obtained if all available dermoscopic criteria are appropriately assessed together with the clinical examination.

Publication types

  • Case Reports

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Diagnosis, Differential
  • Female
  • Humans
  • Keratosis, Seborrheic / pathology*
  • Male
  • Melanoma / pathology
  • Middle Aged
  • Skin Neoplasms / pathology