Radiation dermatitis: pathogenesis, diagnostics and classification. Review

The radiotherapy has remained one of the most effective methods of treating cancer for several decades. Given the nonspecificity of ionizing radiation in relation to cancer cells, in the process of a target organ irradiating, it inevitably passes through the main human barrier organ - the skin, that often leads to such a long-term consequence as radiation dermatitis (RD). RD has been found to be a complication in more than 85% of patients undergoing standard radiotherapy. The pathogenesis of RD is not fully understood and, as a result, there is no “gold” standard for its prevention and treatment. To date, it has been possible to establish a number of features of the induction and development of RD, which explains the ineffectiveness of the available traditional methods of treating wounds and burns. The pathogenesis of RD is determined by the structural features of the skin, the significant contribution of ROS to radiation-induced inflammation, as well as a number of factors, which are usually divided into factors dependent on the patient and factors associated with the source of radiation. It has been shown that the pathogenesis of chronic RD and fibrosis has a number of distinctive features compared to acute RD, in particular, hypoxia is of particular importance during the progression of fibrosis, and chronic RD is accompanied by cell aging. To date, a modern classification of local radiation injuries by severity has been developed, based on developed clinical rating scales, which is important for proper treatment, management and monitoring in clinical practice. Among the methods for diagnosing RD, optical imaging methods occupy a special place, allowing non-invasive detection of various areas of skin damage. Despite significant advances in the study of RD, it is still a serious medical and social problem that significantly worsens the patient’s quality of life. Further study of the mechanisms of RD induction should lead to the development of new approaches in the prevention and treatment of RD.