Introduction. Malignant neoplasms, significantly reducing the duration and quality of life, are one of the main causes of death in the Russian Federation. The results of the review of scientific literature showed: in 2017-2019, there was an increase in absolute values, "rough" and standardized indicators of the incidence of ZNO per 100 thousand population, which was explained by demographic processes and the associated natural aging of the population. However, the COVID-19 pandemic made adjustments and the "rough" incidence rate decreased by 13% in the Russian Federation and by 24.4% in Moscow in 2020 compared to 2019. In our opinion, this trend may be associated with a sharp decrease in the detectability of ZNO, based on a violation of the processes of prevention of non-communicable diseases; prolonged cessation of work on medical examinations and preventive examinations of the population. The data indicate the urgent need to improve the organization of early diagnosis of malignant neoplasms by resorting to primary and secondary prevention tools, and confirms the relevance of the purpose of this study, which is to develop a new methodology for organizing the diagnosis of malignant neoplasms at an early stage and effective routing of patients with suspected ZNO in primary health care as part of the patient's treatment to medical a specialist of any profile. Materials and methods. The description of an experimental algorithm for routing patients with suspected malignant neoplasms in the conditions of primary health care in Moscow (based on the State Medical Institution "GP No. 210 DZM") is presented, and the effectiveness of this algorithm is evaluated. The main problems hindering the improvement of the effectiveness of preventive and diagnostic work of medical workers in terms of oncological alertness are identified. Results. The improvement of the "traditional" algorithm for working with patients with suspected ZNO allowed to significantly increase the motivation of doctors, and, as a result, the indicator of early detection (up to 77.5% in 2021), the overall indicator of the effectiveness of oncopoisk (32.8% of all those referred to the CAOP diagnosis was confirmed). Conclusion. The introduction of experimental methods of work has shown that the effectiveness of preventive work to combat ZNO is affected both by the transfer of the design of directions for diagnostic procedures during the main time of the planned medical appointment (with the delegation of this process to the head of the structural unit), and by the reduction of their terms and territorial remoteness for the patient.