Hypopharynx Cancer Incidence in Kazakhstan: 2017-2021.

OBJECTIVE: The article studies the geographical features of the incidence of hypopharynx cancer (HPC) in Kazakhstan. METHODS: The retrospective study was done for the period 2017-2021. Descriptive and analytical methods of ecoepidemiology were used. Crude (CR), age-specific (ASIR), age-standardized (ASR), equalized incidence rates and approximation were calculated. The dynamics of indicators was investigated using component analysis according to methodological recommendations. The method of drawing up a cartogram based on the determination of the standard deviation (σ) from the mean (x) was applied. RESULT: During the study period, 814 new cases of HPC were registered. The incidence rate decreased from 0.898 (2017) to 0.895 in 2021 and the overall decline was 0.003 per 100,000 population, including due to the age structure - ∑ΔA=+0.04, due to the risk of acquiring illness - ∑ΔR=-0.05 and their combined effect - ∑ΔRA=+0.01. The component analysis revealed that the increase in the number of patients with HPC was mainly due to the growth of the population (ΔP=+37.0%), changes in its age structure (ΔA=+106.1%) and changes associated with the risk of acquiring illness (ΔR=-133.4%). The cartograms were allocated according to the following criteria: low - up to 0.730/0000, average - from 0.73 to 1.180/0000, high - above 1.180/0000. The results of the spatial assessment showed the highest levels of HPC incidence in following regions: Atyrau (1.960/0000) and West Kazakhstan (1.580/0000). CONCLUSION: Thus, this is the first epidemiological study of HPC, which assessed the role of the influence of various factors, including demographic and risk of acquiring illness, on the dynamics of incidence, taking into account gender differences and geographical variability.

Thyroid Cancer in Kazakhstan: Component Analysis of Incidence Dynamics.

Background: The International Agency for Research on Cancer (IARC) reports that 567,000 new cases of thyroid cancer (TC) were registered in the world in 2018, and the age-standardized incidence rate was 6.7 per 100,000. The Global Cancer Observation forecasts a 35% growth in the number of new cases worldwide by 2040. The number of patients with TC in Kazakhstan is also increasing steadily. This investigation was the first epidemiological study of TC trends by component analysis among the population of Kazakhstan. This paper presents the results of the component analysis of TC incidence trends in Kazakhstan. Methods: The study covers primary data of TC cases (ICD 10 ­ C73) registered throughout Kazakhstan from 2009 to 2018. TC incidence trends were evaluated using component analysis according to the methodological recommendations. Results: 5,559 new TC cases were registered during the 10-year study period. The average age of patients was 52.0±0.2 years, the average annual age-standardized rate in 2009-2018 was 3.3±0.20/0000, with a constant upward trend (Т=+6.6%). According to the component analysis results, the increase in incidence was mainly due to the combined effect of the two factors: the increased disease risk (ΔR=+61.7%), and the population growth (ΔP=+15.4%). Conclusion: The noted increase in incidence was mainly caused by the changes in risk factors, such as the worsening environmental aspects and the increase in detection of clinically non-manifesting cases. The results of the study shall be taken into account when planning anticancer activities for TC.