Introduction: Breast cancer is the most common cancer diagnosed in women and has remained a global problem for many decades. 

Aim: To analyze the epidemiological indicators of breast cancer among women of Sumy region during 2016-2020 and to compare the obtained data with the all- Ukrainian ones.

Materials and methods: Data from the National Cancer Registry of Ukraine were used to analyze the epidemiological indicators of breast cancer. Statistical processing of indicators was performed using the analysis of mean values and the method of standard deviation.

Results: The average incidence of breast cancer in Sumy region for 2016-2020 is 75,7±7,24 cases per 100 thousand population, which is higher by 10,2% compared to the average Ukrainian (68,0±4,45 cases per 100 thousand population). During 2016- 2019, there are no clear trends in the dynamics of the incidence rates. However, in 2020 there is a decrease in the Ukraine-wide incidence rate by 14,2%, and in Sumy region – by 22,1% compared to the previous year. The percentage of breast cancer cases detected during preventive examinations during 2016-2020 is higher in Sumy region and is 56,1±2,71% against 46,0±4,74% in Ukraine-wide. This may affect the rate of early detection of lung cancer (stage I-II), which in Sumy region significantly exceeds the average Ukrainian (86,0±2,99% vs. 73,8±1,75%, respectively). The average one-year mortality rate of breast cancer in Ukraine exceeds this rate in Sumy region and is 9,4±0,52% and 7,8±1,21%, respectively. The percentage of coverage with special treatment is almost the same: 80,2±0,57% in Ukraine and 79,8±2,92% in Sumy region.

Conclusions: Sumy region is characterized by higher rates of breast cancer compared to all-Ukrainian rates. In contrast to the incidence rates, the average one-year mortality rate in Sumy region is lower compared to the all-Ukrainian, which may be due to the higher detection rate of breast cancer on preventive examinations and as a result the predominance of the disease in the early stages. The decrease in breast cancer incidence among women in Sumy region in 2020 may be associated with reducing the number of visits to oncologists due to the COVID-19 pandemic and quarantine restrictions. In the near future, this can lead to an increase in the incidence of advanced breast cancer and negatively affect the prognosis of such patients.