BRCA1/BRCA2 MUTATIONS IN BREAST CANCER: CLINICAL SIGNIFICANCE, PROGNOSTAIC VALUE, AND THERAPEUTIC IMPLICATIONS

Anita Strzykala; Igor Szlegiel; Oktawia Gwiaździńska; Jakub  Lewandowski; Denis Myszak

doi:10.31435/ijitss.2(50).2026.5937

Authors

Anita Strzykala Independent Researcher, Szczecin, Poland https://orcid.org/0009-0003-5392-2199
Igor Szlegiel Independent Researcher, Szczecin, Poland https://orcid.org/0009-0000-8271-8945
Oktawia Gwiaździńska Independent Researcher, Szczecin, Poland https://orcid.org/0009-0001-1212-4276
Jakub Lewandowski Independent Researcher, Szczecin, Poland https://orcid.org/0009-0006-2477-8660
Denis Myszak Independent Researcher, Szczecin, Poland https://orcid.org/0000-0001-5275-3141

DOI:

https://doi.org/10.31435/ijitss.2(50).2026.5937

Keywords:

BRCA1, BRCA2, Breast Cancer, PARP Inhibitors, Targeted Therapy, Molecular Diagnostics, Prognosis

Abstract

Objective: The aim of this review article is to present the current state of knowledge regarding BRCA1 and BRCA2 mutations in breast cancer, with particular emphasis on their clinical significance, prognostic value, and therapeutic implications. The paper discusses the biological functions of BRCA genes, the epidemiology of hereditary breast cancer, the role of molecular diagnostics, and contemporary targeted treatment strategies.

Materials and Methods: A narrative review of the scientific literature concerning BRCA1/BRCA2 mutations and breast cancer was conducted. Publications from peer-reviewed medical journals, meta-analyses, clinical guidelines, and clinical trials published between 1998 and 2022 were analyzed. The review included data on epidemiology, molecular biology, prognosis, and modern therapeutic approaches, including PARP inhibitors and platinum-based chemotherapy.

Results: BRCA1 and BRCA2 mutations are among the most significant risk factors for hereditary breast and ovarian cancer. Carriers of BRCA1 mutations more frequently develop triple-negative breast cancer, whereas BRCA2 mutations are more commonly associated with hormone receptor–positive tumors. The presence of these mutations influences the clinical course of the disease, the risk of recurrence, and the selection of therapeutic strategies. The development of PARP inhibitors has significantly improved treatment outcomes in patients with BRCA-mutated breast cancer, both in advanced disease and in early-stage settings. Increasing attention is also being given to prophylactic surgery and treatment individualization.

Conclusions: BRCA1/BRCA2 mutations have substantial prognostic and predictive significance in breast cancer. Advances in molecular diagnostics and targeted therapies enable personalized treatment approaches and improved patient outcomes. Further research is needed to better understand mechanisms of treatment resistance and to identify novel biomarkers predictive of therapeutic response.

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