The impact of COVID-19 on the indicators of the oncological service for breast cancer in Kazakhstan

ABSTRACT

Introduction. According to International Agency for Research on Cancer in 2040, about 3 million new cases of breast cancer (BC) are predicted and about 1 million women are expected to die from this pathology. The aim of the study to assess the impact of COVID-19 on the indicators of the oncological service for breast cancer in Kazakhstan. Material and research methods. The main method was a retrospective study using descriptive, analytical methods of biomedical statistics and data of the Ministry of Health of the Republic of Kazakhstan - form No.7 and 35 regarding BC (ICD 10 - C50) for 2011-2020. Results. For 2011-2020 42,376 new cases of BC and 12,914 deaths from this pathology were registered. The average annual crude incidence rate was 46.4+or-1.10/0000 (95%CI=44.3-48.5), and increased from 40.8+or-0.70/0000 (2011) to 51 .3+or-0.70/0000 in 2019 and then decrease to 44.2+or-0.70/0000 in 2020 (p<0.001). In dynamics, mortality rates tended to (p<0.001) decrease from 16.1+or-0.40/0000 (2009) to 11.9+or-0.40/0000 in 2019 and 11.5+or- 0.40/0000 in 2020, and the average annual crude mortality rate was 14.2+or-0.60/0000 (95%CI=13.1-15.3). Indicators of early diagnosis (stage I-II) improved from 73.4% (2011) to 86.9% in 2019, and decreased to 84.2% in 2020. Proportion of patients with stage III decreased (from 20.9% in 2011 to 8.4% in 2019 and to 10.0% in 2020) and stage IV (from 5.6% to 4.2% and 5.0%, respectively), i.e. neglect rates are declining. The indicators of morphological verification improved from 95.7% to 99.4% over the years. Conclusions. As a result of the analysis, an improvement in the indicators of morphological verification, early diagnosis, a decrease in the neglect and mortality rates were established. The trends in 2011-2019 differed significantly from the period from 2011-2020, which is due to the COVID-19 pandemic on the registration of BC.