The third edition of the NCCN Clinical Practice Guidelines in Oncology:Breast Cancer in 2020 mentions that all patients with relapsed or metastatic breast cancer should be evaluated for germline BRCA1 / 2 mutations to identify candidates for PARP inhibitor therapy. HER2-negative disease states that olaparib and talazoparib are FDA approved, and the team supports use in any breast cancer subtype associated with germline BRCA1 or BRCA2 mutations; positive for HR / HER2-negative breast cancer, if HR positive / HER2-negative and considering treatment to identify Alpelisib plus fulvestrant drug candidates, the PIK3CA mutation should be evaluated by tumor or liquid biopsy. PIK3CA mutation testing can be performed on tumor tissue or ctDNA in peripheral blood (liquid biopsy). If the liquid biopsy is negative, then a tumor tissue test is recommended.

The 2019 China Anti-Cancer Association Guidelines and Standards for Breast Cancer Diagnosis and Treatment lists the characteristics of breast cancer patients recommended for BRCA gene screening. And for those who have known mutation sites in the family, it is recommended to use the first generation sequencing method to detect. For those who do not have a known mutation site in the family or have never tested the BRCA gene in the family, it is recommended to use next-generation sequencing combined with the large fragment deletion detection method to detect all exons, exons and introns of the BRCA1 / 2 gene Sub-connection area ± 20 bp. 

The American Society of Breast Surgeons (ASBrS) urges all breast cancer patients (newly diagnosed or have a personal history) to undergo genetic testing, and should provide genetic testing to patients who have no history of breast cancer in accordance with NCCN guidelines to assess whether they have genetic Sexual cancer risk. Such tests should include BRCA1 / BRCA2 and PALB2, as well as other genetic tests suitable for clinical conditions and family history.