Objective — to study the molecular mechanisms of the development of actinic keratosis (AK) and compare them with Bowen’s disease.
 Materials and methods. A literature review, analysis of national and international protocols for the diagnosis of AK are presented, which meet the selection criteria. We reviewed works with at least one recommendation for AK diagnostic scenario published after 2015. The systematic literature review is based on modern studies containing descriptions of molecular diagnostics of certain proto-oncogenes to establish the final diagnosis. Interdisciplinary guidelines were also reviewed to further explore all possible diagnostic criteria.
 Results and discussion. Until now, the molecular mechanisms of AK development have not been fully studied and grouped into a single review. In most of the sources, only p53 protein was mentioned as the main transcription factor regulating apoptosis. However, recent studies prove a sufficient influence of CD95, which, like p53, induces apoptosis and plays a leading role in the development of AK. All precancerous and malignant neoplasms of the skin arise due to mutations in cells, which cause a violation of apoptosis, but there are still no recommendations and a clear diagnostic algorithm that will allow to quickly establish the final diagnosis and make a choice in favor of this or another method of treatment.
 Conclusions. AK and Bowen’s disease are different stages in the development of the same malignant process, differing in the proliferative activity of cells and the expression of proto-oncogenes CD95, bcl-2, and p16 which can be used as differential diagnostic markers. Thanks to early diagnosis, it is possible to choose the most suitable treatment option, with consideration for modern protocols.