Inclusion Criteria:  Recent progression of TNBC after multiple lines of chemotherapy or of HR+ or HER2+ MBC after multiple lines of endocrine or targeted therapy; No available recommendation for the next treatment regimen; An Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 2; An updated, available pathological HR/HER2 status for metastasis; According to RECIST 1.1 standard, there should be at least one measurable target lesion; The expected survival time is > 3 months; Those aged 18-70 years old; Liver and kidney function and blood routine test meet the following conditions: Neutrophil > 2.0g/l, Hb > 9g / L, PLT > 100g / L; ALT and AST < 2.5ULN; TBIL < 1.5ULN; Cr < 1.0ULN Signing informed consent; Those willing to accept polygenic testing.  Exclusion Criteria:  Patients with multiple primary tumors; Those who are unable to obtain blood samples; Those with a history of immunodeficiency or organ transplantation; Those with abnormal cardiac function or previous history of myocardial infarction or serious arrhythmia; The researchers think it is not suitable to participate in this experiment.