Predictive molecular markers of resistance to chemotherapy in breast cancer

Breast cancer is one of the three most common cancers along with lung and colon cancer. It is a leading cause of cancer deaths in both developing and developed countries. Within 2 decades, neoadjuvant chemotherapy (NAC) has become a standard treatment option in breast cancer. Relevant articles were identified by means of PubMed, Embase, Web of Science, Cochrane Library and Springer Link databases published during the years 2010-2019, describing the role of molecular biomarkers in the assessment of NAC for breast cancer.

Conclusions: The size of the breast primary tumor, the affection of the regional lymph nodes, the degree of tumor differentiation, the expression of hormone receptors, HER2neu, ki67 serve as main criteria for predicting the response to NAC. Preoperative core needle biopsy is the gold standard procedure in cancer diagnostics, in the analysis of predictive biomarkers, particularly uti­lizing histomorphological characteristics. Carrying out a larger number of cycles of NAC as well as correlating the schemes in relation to the immunohistochemical types have a direct influence on obtaining a good response to treatment. Patients with a pathologic complete response had superior survival outcomes compared with patients who had residual disease.