Endocrine therapy is the primary systemic therapy for hormone receptor-positive breast cancer, which runs through the whole process of treatment for early and metastatic breast cancer. The development of new endocrine agents and targeted drugs such as cyclin-dependent kinases 4/6(CDK4/6)inhibitors has improved outcome of patients with hormone receptor-positive breast cancer and changed the treatment landscape. The update of clinical research data provides more treatment options, calling for treatment optimization. Experts had a deep discussion around the hot topics on endocrine therapy of breast cancer, and formulated the\'Expert consensus on endocrine therapy of breast cancer (2023 edition)\'.This consensus is based on research data worldwide and clinical practice experience, with the aims of standardizing clinical diagnosis and optimizing treatment in neoadjuvant, adjuvant and metastatic setting of hormone receptor-positive breast cancer.
内分泌治疗是激素受体阳性乳腺癌的主要治疗手段，贯穿于早期和复发转移乳腺癌治疗的全过程。新型内分泌药物和细胞周期蛋白依赖性激酶4/6（CDK4/6）抑制剂等靶向药物的研发，改善了激素受体阳性乳腺癌患者的预后，改变了治疗格局。然而，临床研究数据的更新，提供更多治疗选择的同时，也产生了新的临床问题。我们结合国内外临床研究数据和实践经验，经讨论后达成本共识，旨在规范内分泌治疗在激素受体阳性乳腺癌新辅助治疗、辅助治疗和复发转移解救治疗中的应用。.

Cyclin-dependent kinases 4/6 (CDK4/6) inhibitors are anti-tumor agents for the treatment of hormone receptor-positive breast cancer. Palbociclib, abemaciclib and dalpiciclib have been approved for the treatment of breast cancer in China. Common adverse effects of CDK4/6 inhibitors include bone marrow suppression, gastrointestinal toxicities, liver dysfunction, and skin or subcutaneous tissue adverse reactions (AEs). The Breast Cancer Expert Group of Chinese Society of Clinical Oncology (CSCO) summarized the incidence, clinical manifestations, and grading of the AEs. This expert consensus reports measures of AE management on the basis of experience of clinical practice and the latest advances worldwide, aiming to guide clinical practice by the way of managing AE and help to choose the best treatment regimen.
细胞周期蛋白依赖性激酶4/6(CDK4/6)抑制剂是治疗激素受体阳性乳腺癌的抗肿瘤药物，其中，哌柏西利、阿贝西利和达尔西利已在中国获得批准用于乳腺癌的治疗。CDK4/6抑制剂常见的不良反应包括骨髓抑制、胃肠道不良反应、肝功能异常、皮肤及皮下组织不良反应等。中国临床肿瘤学会乳腺癌专家委员会共识专家组总结了CDK4/6抑制剂常见不良反应的发生率、临床表现和严重程度分级，结合临床经验并参考国内外研究进展，制定了不良事件的管理措施，形成乳腺癌CDK4/6抑制剂相关性不良反应管理共识，旨在从不良反应管理角度更好地指导临床实践，帮助选择CDK4/6抑制剂最佳治疗方案。.

The introduction of cyclin-dependent kinase (CDK) 4/6 inhibitors has revolutionized the clinical management paradigm of hormone receptor (HR) positive/human epidermal growth factor receptor (HER) 2 negative breast cancer. As of today, CDK 4/6 inhibitors including Palbociclib, Ribociclib, and Abemaciclib have been widely approved by regulatory agencies. Randomized clinical trials demonstrated that CDK 4/6 inhibitors in combination with an aromatase inhibitor (AI) or fulvestrant in the first-, second- or later-line setting for HR positive/HER2 negative locally advanced or metastatic breast cancer led to substantial reduction in the risk of disease progression or death. Adverse effects of treatment were manageable and as or better than expected in terms of patient satisfaction. Considering CDK4/6 inhibitors in combination with endocrine therapy being a novel approach in China clinical practice, the panel developed the consensus comprehensively describing the pharmacology properties, monitoring strategy during treatment and adverse events management, to facilitate greater understanding in Chinese oncologists of a whole new therapeutic class of drug, promote accuracy of clinical decision and help reach the ultimate goal of improving survival and quality of life of the target patient population.
CDK4/6抑制剂为激素受体(HR)阳性人表皮生长因子受体2(HER-2)阴性乳腺癌患者的临床管理模式带来革新。全球上市的CDK4/6抑制剂包括哌柏西利、Ribociclib和阿贝西利。对于HR阳性HER-2阴性局部晚期和转移性乳腺癌，CDK4/6抑制剂联合芳香化酶抑制剂或氟维司群一线或二线及以上治疗均可大幅度降低疾病进展或死亡风险，不良反应可控。鉴于CDK4/6抑制剂联合内分泌治疗在中国的临床应用刚开始起步，国家肿瘤质控中心乳腺癌专家委员会和中国抗癌协会肿瘤药物临床研究专业委员会组织相关领域专家，制定了CDK4/6抑制剂临床应用专家共识，系统性介绍CDK4/6抑制剂的药理学特征、用药监测以及不良事件管理等，以期加深临床肿瘤医师对CDK4/6抑制剂药物的认知，推进临床决策的精准性，达到延长患者生存时间和提高生活质量的最终目标。.