This is a single-arm, open-label, exploratory clinical study
previous bilateral oophorectomy, or age ≥60 years; or
Age <60, natural postmenopausal status (defined as spontaneous cessation of regular menstruation for at least 12 consecutive months without other pathological or physiological causes), E2 and FSH at postmenopausal levels; 2. All patients had estrogen receptor (ER) positive (> 10%), HER2 receptor-negative invasive breast cancer regardless of PR expression level. Follow the 2018 ASC-CAP HER2 Negative Interpretation Guidelines. Immunohistochemical (IHC) scores of 0+ or 2+ and in situ hybridization (ISH) test negative were confirmed by pathology laboratory (HER-2/CEP17 ratio < 2.0); 3. Patients with initial treatment of stage II-III whose tumor stage meets AJCC 8th edition standard; 4. There is no known severe hypersensitivity to compounds or endocrine therapy similar to Darcilil or darcilil excipients.
Bone marrow function ANC ≥ 1.5×109/L (no growth factor used within 14 days); PLT ≥ 100×109/L (no corrective therapy used within 7 days); Hb ≥ 100 g/L (no corrective therapy used within 7 days);
Liver and kidney function TBIL≤1.5×ULN; ALT and AST≤3×ULN (ALT and AST≤5×ULN in patients with liver metastasis); BUN and Cr≤1.5×ULN and creatinine clearance ≥50 mL/min (Cockcroft-Gault formula);
Previously received any form of anti-tumor therapy (chemotherapy, radiotherapy, molecular targeted therapy, endocrine therapy, etc.);
At the same time receive any anti-tumor treatment other than that prescribed in other protocols;
Bilateral breast cancer, inflammatory breast cancer or ocessive breast cancer;
Stage IV breast cancer;