EPIDEMIOLOGICAL PARALLELS OF RECTAL CANCER INCIDENCE IN KAZAKHSTAN AND KYRGYZSTAN

Background and Objectives: Of the colorectal malignant tumors, 30 percent will arise in the rectum. The incidence of rectal cancer is increasing with the change of diet habit and genetic factors. The etiology of colon and rectal cancer is a bit different. The risks of distal colon and rectal cancer are more likely to be related to environmental factors, such as polluted surface water sources, alcohol consumption, and habitual smoking. The lack of great change in the incidence of rectal cancer might be due to weaker associations with such lifestyle factors. The study was to analyze the incidence of rectal cancer in the Central Asian republics – Kazakhstan and Kyrgyzstan.
Methods: Dates of rectal cancer patients during 2000-2010 were collected from population-based cancer registry in Kazakhstan and hospital-based registry in Kyrgyzstan. Incidence and mortality of rectal cancer were calculated and analyzed.
Results: The crude incidence of rectal cancer in Kazakhstan and Kyrgyzstan from 2000 to 2009 were 6.8 per 100 000 (7.4 per 100 000 in males, 6.2 per 100 000 in females) and 3.3 per 100 000 (3.2 per 100 000 in males and 3.4 per 100 000 in females), respectively. The incidence of rectal cancer ranked seventh (Kazakhstan) and eight (Kyrgyzstan) respectively among all cancers.The incidence of rectal cancer was increased with age at the both countries. High incidence rate of rectal cancer was registered at the Russian ethnic group, compare with native Kazakhs and Kyrgyzs. 
Conclusions: The incidence of rectal cancer is high in Kazakhstan compared to Kyrgyzstan. There are geographical and ethnic variabilities in rectal cancer incidence. High incidence rate of rectal cancer was registered in the North region of Kazakhstan, where predominance Russian population. Studies on the prevention and treatment of rectal cancer should be enhanced

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