Abstract:

Improving the efficiency of treatment of locally distributed forms of breast cancer (BC) patients is relevant. The aim of the study: to determine the possibility of increasing the efficiency of treatment of patients with locally distributed BC by supplementing it with the determination of the expression of TOP2 alpha and beta-tubulin III genes in the primary tumor during various chemotherapy regimens. Method. 139 patients with locally distributed BC were examined. Patients received 2-4 courses of neoadjuvant chemotherapy (NAChT) according to the TC (docetaxel + cyclophosphamide) and TAC (docetaxel + doxorubicin + cyclophosphamide) regimens, subsequent surgical intervention and 2–4 courses of AchT according to the FAC regimen. Immunohistochemical (IHCh) study of the levels of estrogen receptors (ER), progesterone (PR), epidermal growth factor (HER2) in tumors was conducted. The expression of TOP2 alpha and beta-tubulin class III genes was determined using PCR. Statistical data processing was performed using the program Stastistica for Windows 6. 0, Excel. Results. In the third cycle of chemotherapy, patients were transferred from the TC scheme to the TAC scheme. The frequency of the FPR increased 4 times in the group of patients with a triple negative tumor subtype compared with patients with luminal B. A combination of low expression of the class III beta-tubulin gene with high expression of TOP2 alpha in tumor tissue was found in 64.5 % of patients treated according to the TAC + cross over regimen and in 56.3 % of cases according to the TC regimen. A change in the receptor status of MLN after NAChT was detected in some cases. Conclusions. The combination of high expression of TOP2 alpha with low expression of class III beta-tubulins can be considered as a predictive sign of full pathomorphological response when using taxane-containing locally distributed BC. These markers can be recommended for determination in MLN (along with definition of ER, PR, HER2) in order to increase the effectiveness of AchT.

Keywords: