Actinic Keratosis—Can Dermoscopy or RCM Differentiate AK (Not Full Thickness Atypia) from Full-Thickness Atypia/Invasive SCC?
Purpose of Review
Actinic keratosis (AK) is the most common sun-induced preneoplastic lesion, and together with photo-aging and skin cancer, it places a huge burden on healthcare systems. The clinical distinction between AK and incipient squamous cell carcinoma (SCC) can be difficult, and therefore, clinical diagnosis is not always reliable and certain. Skin biopsies are sometimes mandatory, and physicians must be aware of the importance of accurate diagnosis and management, as other malignant neoplasms (melanoma, basal cell carcinoma) cannot always be reliably distinguished from AK, especially when pigmented and inflamed.
Although histopathology remains the gold standard for differentiation of AK from SCC, some non-invasive optical technologies such as dermoscopy and reflectance confocal microscopy have recently been applied to enhance clinical diagnosis accuracy and to obtain an in vivo characterization of these lesions.
The combination of dermoscopy with reflectance confocal microscopy improves the clinical assessment and diagnosis of equivocal keratinizing tumors, allows the selection of the most suspicious areas for biopsy, and permits non-invasive determination of treatment outcomes.
KeywordsDermoscopy Reflectance confocal microscopy Actinic keratosis Squamous cell carcinoma Cancerization field
Research at the Melanoma Unit in Barcelona is partially funded by Spanish Fondo de Investigaciones Sanitarias grants 15/00956 and 15/00716; co-financed by European Development Regional Fund “A way to achieve Europe” ERDF; AGAUR 2014_SGR_603 of the Catalan Government, Spain; the European Commission under the 6th Framework Programme, Contract No. LSHC-CT-2006-018702 (GenoMEL); the European Commission under the 7th Framework Programme, Diagnoptics; the National Cancer Institute (NCI) of the US National Institute of Health (NIH) (CA83115); and a grant from “Fundació La Marató de TV3, 201331-30,” Catalonia, Spain and a Research Grant from Asociación Española Contra el Cancer.
Compliance with Ethical Standards
Conflict of Interest
The authors declare that they have no conflict of interest.
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
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