Neoadjuvant polychemotherapy (NPCT) is a predictor of the impact of systemic therapy on breast cancer (BC) biology. Currently, the sequence of drug administration is receiving particular attention.

OBJECTIVE

To analyze factors influencing pathological response rates, treatment resistance, and long-term survival in patients with hereditary BC after NPCT with anthracycline- and Taxane-containing regimens.

MATERIAL AND METHODS

The study cohort (115 BC patients treated between 2014 and 2023) was divided into two groups, in which the outcomes of NPCT with anthracycline- and taxane-containing agents were examined. The analysis of immediate outcomes included determining the overall objective response (OR) rate and pathological complete regression (pCR). For all parameters p value of ≤0.05 was considered statistically significant.

RESULTS

In patient with BRCA1-associated BC, clinical complete regression was observed in all cases after Anthracycline therapy, while in the Taxane group, primary tumor growth was noted in 4 cases (p=0.34). In Taxane group pCR was 52.4%, while in Anthracycline it was 50% (p=0.3). In patient with BC without mutation, the OR and pCR rates were slightly higher in the Taxane group: 33.3% versus 31.1% (p=0.82) and 17.8% versus 13.3% (p=0.5), respectively. In Taxane group, local tumor progression was noted in 3 patients (p=0.3). Triple-negative BC was a factor associated with achieving pCR. When analyzing factors influencing long-term survival in patients with hereditary BC, locally advanced BC was the only predictor of worse 3- and 5-year survival.

CONCLUSION

Triple-negative tumor type was the only predictor of complete tumor regression, and advanced stage was the only factor associated with worse overall survival. Identifying chemotherapy resistance factors in hereditary and BRCA1-positive breast cancer requires further research.