Related Experiment Video
Updated: Jul 15, 2026

Anterior High-Resolution Optical Coherence Tomography in the Diagnosis and Therapeutic Monitoring of Ocular Surface Squamous Neoplasia
Published on: August 9, 2024
Actinic keratosis is an early in situ squamous cell carcinoma: a proposal for reclassification
J Röwert-Huber1, M J Patel, T Forschner
1Department of Dermatology, Charité, Skin Cancer Center Charité, University Hospital of Berlin, Berlin, Germany.
Abstract:
The term actinic keratosis (AK) describes a sun-induced, clinical erythematous lesion covered with scale, but does not provide an understanding of the biology or histopathology of the lesion. Consequently, several classification systems for AK have been suggested, but as yet no consensus has been reached. These systems strive to correlate the pathological and clinical features to better provide physicians with the most accurate information to enable correct decisions to be made regarding treatments, Prognosis and metastatic potential. AK is a clinical description that has a histological diagnosis consistent with squamous cell carcinoma (SCC) in situ. We recommend an AK classification system that describes these lesions as squamous cell carcinomas (SCCs), using the terminology 'early in situ SCC Type AK I', 'early in situ SCC type AK II' and 'in situ SCC Type AK III', there by giving clinicians better guidance for diagnosis and specific treatment recommendations.
Related Concept Videos
Skin Cancer
Basal Cell Carcinoma (BCC): BCC is the most common type of skin cancer, accounting for about 80% of cases. It typically develops in...
Cellular Adaptation IV: Dysplasia and Metaplasia
Renewal of Skin Epidermal Stem Cells
Clinical Applications of Epidermal Stem Cells
Cells of the Epidermis
The cells in all these layers except the stratum basale are called keratinocytes, a type of cell that manufactures and stores the protein keratin. The keratinocytes in the stratum corneum are dead and regularly slough away, being replaced by cells from...
Classification of Epithelial Tissues: Stratified Epithelium

