Effectiveness and Safety of Different Treatment Regimens in Patients With ESR1-mutated HR+/HER2-advanced Breast Cancer After Failure of Prior Endocrine Therapy: a Prospective, Non-interventional, Real-world Study
This is a prospective, non-interventional real-world study to observe the efficacy and safety of different treatment regimens in patients with ESR1-mutated HR+/HER2-advanced breast cancer after failure of endocrine therapy. Epidemiological data, efficacy and safety measures will be collected for each subject. Data on efficacy and safety assessment indicators will be collected every 2-3 months until disease progression, receipt of a new anti-tumour treatment modality, death, loss to follow-up, and arrival at the data collection cut-off date. The cut-off date for data collection is defined as 8 weeks after completion of 6 visits for each subject, or 4 weeks after treatment discontinuation and subject discontinuation/withdrawal. Subjects receiving a different treatment regimen remained subject to assessment of safety indicators 4 weeks after discontinuation of the original treatment regimen.
• 1\. must have a histologically or cytologically confirmed diagnosis of breast cancer with evidence of locally advanced disease unsuitable for excision or radical radiotherapy, or evidence of metastatic disease unsuitable for radical treatment.
• 2\. female ≥ 18 years of age
• 3\. female subjects must be postmenopausal (meeting any of the following criteria is sufficient) a) Has undergone oophorectomy. b) Age ≥ 60 years. c) 40 years old \< age ≤ 60 years old with 1 year of menopause. d) Age \<60 years and receiving ovarian suppression therapy.
• 4\. ER-positive and HER2-negative status and ESR1-mutation positive must be confirmed.
• 5\. must have progressed on at least one line of endocrine therapy prior to enrollment, including monotherapy or combination therapy.
• 6\. have normal organ function (as assessed by the investigator).