In applying modern therapies the knowledge about the mechanisms of the emergence of diseases is used more frequently and more effectively, reaching to their genetic background. The concept of personalized medicine derives from the assumption that there is no single definition of a disease and its causes. It is also necessary to understand and know the differences between people suffering from a particular disease, making it possible to match the appropriate treatment to specific groups of patients.

Based on this assumption, scientists design solutions, the effectiveness of which depends on the precise definition of the mechanism of a disease, using specific markers and determining the phenotype and genotype characteristics of a patient. With such precision you can select an appropriate medical treatment for an individual patient at the right time, increasing significantly the chance of a successful treatment. Hence the reasonable definition that it is a "tailor made" treatment. In clinical practice, this means inseparability of the process of molecular diagnostics from the therapy and monitoring of the treatment process.