Study of prostate cancer prevalence in Kazakhstan

Abstract

Introduction. Prostate cancer is the second leading cause of cancer death worldwide, including developed countries. There are epidemiological studies on the prevalence of this disease in Central Asia. However, a study about the prevalence of prostate cancer depending on ethnicity in Kazakhstan was not conducted yet. Objective. To assess the incidence rates of prostate cancer in relation to ethnicity, age and morphological type of tumour (in Kazakhstan). Methods. This is a retrospective study of morphologically verified cases of prostate cancer, performed on 7082 patients during the period 2015-2019. According to ethnicity, the patients were subdivided into the following groups: Central Asians, Slavs, and other nationalities. Four categories were identified by age: <60 yo, 60-69 yo, 70-79 yo and 80+ yo. The information on the age difference, social status, stages of the malignant process, morphological type of cancer was collected and analysed. The age-standardized incidence rate of prostate cancer was calculated depending on ethnicity. All statistical calculations were performed using SPSS software (version 22.0, IBM SPSS Inc., Chicago, Illinois, USA). A p value < 0.05 was considered statistically significant. Results. The mean age of the patients was 69.04±8.5 years. Among 7082 patients, 61.6% were Slavs, 35.01% Central Asians and 3.37% other ethnic groups. Prostate cancer prevailed in the age group 60-69 yo in 41.9% cases, which was higher among Slavs compared to the Central Asians (p≤0.05). The average annual increase in the disease incidence was 2.1%. There was no significant increase in the incidence of prostate cancer in the age groups: <40 yo (r = 0.41), 40–49 y0 (r = 0.31), +80 yo (r = 0.32). Stage II of the tumour process was the most diagnosed in the total number of cases (N = 2856), the highest prevalence being found among Slavs (40.66%) (p ≤ 0.05). Adenocarcinoma was the most frequently detected type of tumour (97.37%) in all ethnic groups. Conclusions. The results of the study showed there was a relatively low increase in the incidence of prostate cancer in the Kazakhstan population between 2015-2019. A high incidence of prostate cancer among men of Slavic nationality than among Central Asians was determined. These findings indicate the importance of the early diagnosis of prostate cancer, especially in ethnic groups with a higher incidence of the disease.

Keywords

• prostate cancer
• ethnicity
• incidence
• mortality
• cancer stage