Homologous Recombination Repair Pathway Gene Mutation Spectrum in Chinese Breast Cancer Patients

The main questions it aims to answer are:

• What is the mutation spectrum of homologous recombination repair pathway genes in Chinese breast cancer patients?
• Does homologous recombination repair pathway gene mutation have an impact on patient outcome (breast cancer recurrence, neoadjuvant chemotherapy efficacy, treatment decisions, etc.) ? There is no intervention on participants, but all participants will be given regular follow-up post surgery according to ASCO guidelines.

Inclusion criteria

• Pathology-confirmed breast cancer patients who meet at least one of the criteria below:

• Triple-negative breast cancer
• Age ≤ 50 years
• Male breast cancer
• With personal or family history of malignancy: breast cancer, ovarian cancer, prostate cancer, pancreatic cancer, other malignancies
• HER-2 negative recurrent or metastatic breast cancer
• HER-2 negative high-risk breast cancer:

A: Neoadjuvant phase: non-pathological complete response for triple-negative breast cancer; non-pathological complete response AND CPS+EG score ≥ 3 for hormone receptor positive breast cancer B: Adjuvant phase: ≥ pT2 or ≥ pN1 for triple-negative breast cancer; ≥ 4 lymph node metastasis for hormone receptor positive breast cancer

• Having been or intended to be tested for germline and (or) somatic homologous recombination repair gene mutations
• Consent to providing medical charts and homologous recombination repair gene testing results, and being cooperative for long-term follow-up

Exclusion criteria

• Homologous recombination repair gene testing results unavailable
• Other factors deemed by the investigators that may sabotage the study