RESUMEN
In recent years, many studies were dedicated to the search for genetic markers in thyroid malignancies, including papillary thyroid cancer. This study was designed to investigate the prevalence of BRAFV600E mutation in the PTC in the Kazakh population, to evaluate the relationship between BRAF V600E mutation status and the clinicopathological features of PTC. Besides, we aimed at assessing of the relationship between the high proliferation index and the clinicopathological features of PTC and also between the concomitant coexistence of BRAFV600E and the high proliferative index with clinicopathological features of PTC. We carried out a cross-sectional study on 123 patients with PTC of Kazakh ethnicity and analyzed their clinical, laboratory, and genetic findings. The study groups were pooled based on the presence of mutated or wild-type BRAFV600E and quantitative assessment of Ki-67 marker expression. In the course of our study, we found that the age of patients from the group of BRAF gene mutation was significantly higher than that of patients from the wild-type group (48.63 ± 14.07 years versus 40.23 ± 14.34 years) (t = - 3.257; p = 0.001). Correlation analysis between BRAF mutation, Ki-67 expression, their combination and various clinical and pathological parameters in PTC patients showed that older age was positively correlated with higher frequency of mutant BRAF gene (r = 0.284; p < 0.001), while more advanced stage of tumor was positively correlated with higher expression of Ki-67 (r = 0.307; p < 0.001). To understand the significance of detecting the BRAFV600E mutation and an increased level of Ki-67 expression in the choice of patient therapy tactics, larger studies are required with patient survival as one of the primary outcomes.