Dermatoscopy

Dermoscopy of basal cell carcinoma CME

Created 2008.

Learning objectives

  • Describe dermoscopic features of basal cell carcinoma

Introduction

Dermoscopy is useful to distinguish pigmented basal cell carcinoma from other pigmented lesions. There are specific features that help to distinguish these. Pigment may be grey, brown, blue or black. They are rarely completely pigmented in white-skinned individuals.

Pigmented basal cell carcinoma

The dermoscopic features of pigmented basal cell carcinoma include:

  • Absence of pigment network
  • Linear and arborising (branch-like) telangiectasia
  • Structureless or leaf-like areas on the periphery of the lesion
  • Large blue-grey ovoid nests or blotches
  • Multiple blue-grey globules
  • Specks of brown and grey pigment
  • Spoke wheel areas (radial projections from a well circumscribed dark central hub)
  • Focal ulceration
Pigmented basal cell carcinoma

In some cases, it may be difficult to distinguish deeply pigmented or even non-pigmented basal cell carcinoma from melanoma.

Non-pigmented basal cell carcinoma

Non-pigmented basal cell carcinomas are much more common than pigmented basal cell carcinoma. They contain flecks of grey colour.

Experienced dermoscopists can often diagnose superficial basal cell carcinomas by their typical bluish-pink colour, asymmetrical arborising vessels and focal ulceration. Slight scaling and white areas of regression may also be present. Chrystalline structures, i.e. white shiny lines, strands and larger irregular-shaped white areas, are common in all histological types of basal cell carcinoma. These short parallel or disordered lines and roundish white structures are often only visible on polarised dermoscopy.

Nodular basal cell carcinomas lose the blue hue and instead have a white rim around central ulceration. Milia may be present. Disordered and streaky crystalline structures may be seen.

Non-pigmented basal cell carcinoma

Activity

Imiquimod cream has restricted subsidy by PHARMAC for treating certain superficial basal cell carcinomas (New Zealand, September 2008). Observe the inflammatory response to treatment using dermoscopy.

 

Acknowledgements

Online continuing medical education designed for health professionals and students.

Learning objectives will be listed for each topic.

Begin course 

Acknowledgements  

Developed in collaboration with the University of Auckland Goodfellow Unit in 2007.

Author: Hon A/Prof Amanda Oakley, Dermatologist, Hamilton, New Zealand, 2008.  

Images have been sourced from the following:

Course contents

  

 goodfellow unit logo

 

Related Information

References:

  • Menzies SW. Dermoscopy of pigmented basal cell carcinoma. Clin Dermatol. 2002 May-Jun;20(3):268-9. Medline.
  • Menzies SW, Westerhoff K, Rabinovitz H, Kopf AW, McCarthy WH, Katz B. Surface microscopy of pigmented basal cell carcinoma. Arch Dermatol. 2000 Aug;136(8):1012-6. Medline.
  • Kreusch JF. Vascular patterns in skin tumors. Clin Dermatol. 2002 May-Jun;20(3):248-54. Medline.

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