A Prospective, Multicenter, Randomized Phase III Non-Inferiority Trial Evaluating Omission of Adjuvant Radiotherapy in Low- and Intermediate-Risk ER-Positive HER2-Negative Ductal Carcinoma In Situ Following Breast-Conserving Surgery
试验速览
- 阶段
- 3 期
- 状态
- 招募中
- 入组人数
- 636
- 试验地点
- 1
- 主要终点
- Ipsilateral Breast Tumor Recurrence (IBTR)
研究概览
简要总结
This is a prospective, multicenter, randomized, open-label, phase III non-inferiority trial designed to evaluate whether omission of postoperative radiotherapy is clinically acceptable in patients with low- and intermediate-risk ductal carcinoma in situ (DCIS) following breast-conserving surgery. Eligible patients include women aged ≥40 years with ER-positive, low- or intermediate-grade DCIS, tumor size ≤2.5 cm, negative surgical margins ≥3 mm, absence of comedo necrosis, and screen-detected unifocal disease. Patients will be randomized to postoperative observation alone or adjuvant radiotherapy. The primary endpoint is 5-year ipsilateral breast tumor recurrence (IBTR).
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Treatment
- 盲法
- None
入排标准
- 年龄范围
- 40 Years 至 —（Adult, Older Adult）
- 性别
- Female
- 接受健康志愿者
- 否
入选标准
- •Female patients aged ≥40 years；
- •Histologically confirmed low- or intermediate-grade ductal carcinoma in situ (DCIS) without invasive carcinoma, including incidental DCIS identified within benign breast lesions；
- •Tumor size ≤2.5 cm on final pathology；
- •Negative surgical margins ≥3 mm, including margins obtained after re-excision；
- •Estrogen receptor-positive disease (ER ≥10%) with planned endocrine therapy using tamoxifen；
- •Unifocal lesion；
- •Absence of comedo necrosis；
- •Screen-detected disease without bloody nipple discharge or palpable mass；
- •Clinically node-negative disease；
- •Patients randomized to the radiotherapy arm must initiate radiotherapy within 3 months after surgery；
- •Central pathology review by the participating institution required；
- •Ability to understand and willingness to sign written informed consent.
排除标准
- •Known BRCA1 or BRCA2 germline mutation carriers (genetic testing not mandatory)；
- •Contraindications to radiotherapy, including active connective tissue disease；
- •Active infection requiring systemic treatment；
- •Bilateral breast cancer or prior contralateral breast cancer；
- •Severe uncontrolled comorbidities, including significant cardiac, pulmonary, hepatic, renal, hematologic, or psychiatric disorders；
- •History of other malignancies, including thyroid cancer, except adequately treated basal cell carcinoma of the skin or cervical carcinoma in situ；
- •Prior thoracic radiotherapy；
- •Pregnant or breastfeeding patients；
- •Estimated life expectancy ≤5 years；
- •Poor compliance or inability to adhere to study follow-up requirements.
研究组 & 干预措施
Adjuvant Radiotherapy
Patients will receive postoperative adjuvant radiotherapy after breast-conserving surgery in addition to endocrine therapy.
干预措施: Adjuvant Radiotherapy (Radiation)
Radiotherapy Omission
Patients will undergo observation alone after breast-conserving surgery and receive standard follow-up and endocrine therapy.
干预措施: tamoxifen (Drug)
Adjuvant Radiotherapy
Patients will receive postoperative adjuvant radiotherapy after breast-conserving surgery in addition to endocrine therapy.
干预措施: tamoxifen (Drug)
结局指标
主要结局
Ipsilateral Breast Tumor Recurrence (IBTR)
时间窗: 5 years
Defined as recurrence of invasive carcinoma or DCIS in the ipsilateral breast.
次要结局
- Local-Regional Recurrence (LRR)(5 years)
- Breast Cancer-Specific Survival (BCSS)(5 years)
- Overall Survival (OS)(5 years)
- Distant Metastasis-Free Survival (DMFS)(5 years)
- Contralateral Breast Cancer Events(5 years)
- Mastectomy-Free Survival(5 years)
- Second primary malignancies(5 years)
- Acute and Late Toxicities(5 years)
- Quality-of-Life Assessed by the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (EORTC QLQ-C30)(5 years)
- Quality-of-Life Assessed by the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Breast Cancer Module 23 (EORTC QLQ-BR23)(5 years)