The conducted analysis showed statistically significant differences in the p-values of BIRC1, BIRC6, and BIRC8 genes expression in patients with a primary tumor size ≤ 20 mm (T1) and patients with primary tumor size > 20 mm but ≤ 50 mm (T2) as well as patients from the T1 group and patients with whose primary tumor size was greater than 50 mm (T3), and there was no statistically significant difference in the level of expression of this gene in patients classified as T2 and T3 taking into account the size of the tumor. The gene discussed is BIRC8; the disease is neoplasm.