Summary
Definition
History and exam
Key diagnostic factors
- presence of risk factors
- presence since birth
- asymmetrical, indistinct or irregularly bordered, variably coloured papules with diameter >5 mm
- history of change in shape and colour
- asymptomatic (usually)
- multiple lesions
- flat, brown macule
- dome-shaped papule
- light brown background with speckled darker brown spots within
- blue-grey dome-shaped papule
- central pink-to-brown papule with a surrounding depigmented white ring
- pinkish-brown papule
Risk factors
- genetic predisposition
- ultraviolet exposure
- fair skin
- age: older children and young adults
Diagnostic investigations
1st investigations to order
- dermatoscopy
Investigations to consider
- non-invasive imaging technologies
- total body photography
- biopsy
Emerging tests
- whole genome sequencing
- pigmented lesion assay (PLA)
Treatment algorithm
clinically benign
clinically suspicious for melanoma
Contributors
Authors
Jason B. Lee, MD

Professor of Dermatology & Cutaneous Biology
Clinical Vice-Chair
Director of Dermatopathology Fellowship
Director of Pigmented Lesion Clinic
Thomas Jefferson University
Philadelphia
PA
Disclosures
JBL declares that he has no competing interests.
Acknowledgements
Dr Jason B. Lee would like to gratefully acknowledge Dr Laurel R. Schwartz, a previous contributor to this topic.
Disclosures
LRS declares that she has no competing interests.
Peer reviewers
Craig G. Burkhart, MD
Clinical Professor
Department of Medicine
Medical College of Ohio
Toledo
OH
Disclosures
CGB declares that he has no competing interests.
Mark Hurt, MD
Dermatologist
Cutaneous Pathology
WCP Laboratories
Missouri
MO
Disclosures
MH declares that he has no competing interests.
Veronique Bataille, MBBS
Consultant Dermatologist
West Herts NHS Trust and King's College London
London
UK
Disclosures
VB declares that she has no competing interests.
Differentials
- Melanoma
- Seborrhoeic keratosis
- Solar lentigo
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