Summary
Definition
History and exam
Key diagnostic factors
- single or multiple scaly macules or plaques
- scaly lesions with a hyperkeratotic surface
- well-defined, scaly, brown lesions
- lesions resembling seborrheic keratosis, melanocytic nevus, and early malignant melanoma
- hypertrophic conical-shaped protuberances growing from the surface of the skin
- scaly red roughness with induration, fissuring, and ulceration of the lower lip and the vermilion border
- lesion on sun-exposed area of body
- skin-colored, papillomatous, elevated wartlike papules
- plaques with very mild scale over very thin shiny skin
- violaceous well-defined papules with fine white lines on the surface
Other diagnostic factors
- evidence of sun damage to skin
- pruritus or bleeding
Risk factors
- chronic exposure to UVB radiation
- light-colored skin, freckling, and albinism
- age >40 years
- male sex
- immunocompromise
- xeroderma pigmentosum
Diagnostic tests
Tests to consider
- dermoscopy
- skin biopsy
Treatment algorithm
confluent scalp lesions
head and face lesions, excluding periorbital, actinic cheilitis, and confluent scalp lesions
periorbital
actinic cheilitis
back of hands
below the knee
Contributors
Authors
Brian Berman, MD, PhD

Professor Emeritus of Dermatology and Cutaneous Surgery
University of Miami Miller School of Medicine
Miami
Skin & Cancer Associates, LLP
Co-Director
Center for Clinical and Cosmetic Research
Aventura
FL
Disclosures
BB is, or has been, a paid consultant/advisor for Almirall (manufacturer of tirbanibulin), Lemonex, Berg/BPGBio Pharma, Novartis, Aiviva, Ferndale, Sensus, Novan, Pierre Fabre (manufacturer of 5-FU), Biofrontera (manufacturer of ALA), SUN (manufacturer of ALA), LEO (manufacturer of ingenol mebutate - removed from market), Sirnaomics, Menlo, Sonoma, PHD Biosciences, Birch BioMed, Mediwound, Mino Labs, and Thirona. He has been a speaker for Almirall (manufacturer of tirbanibulin), LEO (manufacturer of ingenol mebutate), and Sensus. His institution has received investigator funding from Biofrontera (manufacturer of ALA), LEO (manufacturer of ingenol mebutate), Pulse, Sirnaomics, Menlo, Birch BioMed, and Mediwound. BB has stock options in Thirona and Mino Labs.
Sadegh Amini, MD

Dermatologist
Skin and Cancer Associates
Voluntary Assistant Professor
Department of Dermatology and Cutaneous Surgery
University of Miami
Miller School of Medicine
Miami
FL
Disclosures
SA has been compensated by Primus Pharmaceuticals, Inc. for being a member of the clinical advisory board.
Peer reviewers
David S. Cassarino, MD, PhD
Assistant Professor
Departments of Pathology and Dermatology
UCLA
Los Angeles
CA
Disclosures
DSC declares that he has no competing interests.
Christopher Shea, MD
Dermatopathology Fellowship Director
University of Chicago
Section of Dermatology
Chicago
IL
Disclosures
CS declares that he has no competing interests.
Differentials
- Squamous cell carcinoma (SCC) in situ (Bowen disease)
- Invasive SCC
- Keratoacanthoma
More DifferentialsGuidelines
- Focused update: guidelines of care for the management of actinic keratosis
- Guidelines of care for the management of actinic keratosis
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