Trends of Colorectal Cancer Incidence in Kazakhstan

Background and objective:

Colorectal cancer (CRC) remains one of the most widespread human malignancies. The aim of this study was to study trends of the incidence of CRC in Kazakhstan.

Materials and Method:

This retrospective study was done using descriptive and analytical methods of oncoepidemiology.

Results:

During the study period from 2009 to 2018, 28,950 new cases of CRC were recorded, 13,779 (47.6%) cases were allocated to men and 15,171 (52.4%) to women. It was found that the incidence rate of CRC increased from 14.79 (2009) to 17.72 in 2018 and the overall growth was 2.93 cases per 100,000. This increase was due to the age structure – ∑Δ_A=+1.42, the risk of acquiring illness – ∑Δ_R=+1.31, and their combined effect – ∑Δ_RA=+0.20. The component analysis results revealed that the increase in the number of patients with CRC was mainly due to the growth of the population (ΔP=+37.7%), changes in age structure (Δ_A=+26.6%), and changes associated with the risk of acquiring illness (Δ_R=+24.6%). The number of patients (both sexes) was increasing in many regions largely due to the influence of the age structure of the population. In addition, it was found that growth in the number of patients in most regions, both men and women, was associated primarily with the risk of acquiring illness.

Conclusion:

The findings of the current study showed increasing trends in the incidence of CRC in all regions of the country. These changes were mainly influenced by demographic factors (population size and age structure), risk of acquiring the disease, and their combined effect.

Impact of Screening on Breast Cancer Incidence in Kazakhstan: Results of Component Analysis

OBJECTIVE

The study is to conduct a component analysis of the dynamics of the incidence of BC (BC) in Kazakhstan, taking into account regions.

METHODS

Primary data were for registered patients with BC (ICD 10 - C50) in the whole country during the period of 2009-2018. Evaluation of changes in BC incidence in the population of Kazakhstan was performed using component analysis according to the methodological recommendations.

RESULTS

The study period, 40,199 new cases of BC were recorded. The incidence rate increased from 39.5 (2009) to 49.6 in 2018 and the overall growth was 2.8 per 100,000 population of female, including due to the age structure - ∑ΔA=+2.99, due to the risk of acquiring illness - ∑ΔR=+6.82 and their combined effect - ∑ΔRA=+0.31. The component analysis revealed that the increase in the number of patients with BC was mainly due to the growth of the population (ΔP=+31.1%), changes in its age structure (ΔA=+18.0%) and changes associated with the risk of acquiring illness (ΔR=+41.0%). The increase in the number of patients in the regions of the republic is associated with the influence of demographic factors and with risk factors for getting sick, including mammographic screening.

CONCLUSION

Thus, as a result of the component analysis, the role of the influence of demographic factors and the risk of acquiring illness on the formation of the number of patients and the incidence of BC was evaluated, while geographical variability was established. This research was the first epidemiological study of the dynamics of BC in the regional context by the method of component analysis in the population of Kazakhstan. The implementation of the results of this study is recommended in management of anticancer activities for BC.