A Single-Center Prospective Phase II Study Evaluating the Safety of Omission of Adjuvant Radiotherapy in Young Patients With Low-Risk Ductal Carcinoma In Situ After Breast-Conserving Surgery
Trial Snapshot
- Phase
- Phase 2
- Status
- Recruiting
- Sponsor
- Fudan University
- Enrollment
- 234
- Locations
- 1
- Primary Endpoint
- Ipsilateral Breast Tumor Recurrence (IBTR)
Study Overview
Brief Summary
This is a single-center, prospective phase II clinical study designed to evaluate whether omission of postoperative radiotherapy is clinically acceptable in young patients with low-risk ductal carcinoma in situ (DCIS) following breast-conserving surgery. Eligible patients include women younger than 40 years with low- or intermediate-grade DCIS, tumor size ≤1 cm, negative surgical margins ≥3 mm, absence of comedo necrosis, and unifocal screen-detected disease. Patients in the radiotherapy omission cohort will undergo close surveillance after surgery, with endocrine therapy permitted according to physician discretion. The primary endpoint is 5-year ipsilateral breast tumor recurrence (IBTR).
Study Design
- Study Type
- Interventional
- Allocation
- Na
- Intervention Model
- Single Group
- Primary Purpose
- Treatment
- Masking
- None
Eligibility Criteria
- Ages
- — to 40 Years (Child, Adult)
- Sex
- Female
- Accepts Healthy Volunteers
- No
Inclusion Criteria
- •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 ≤1 cm on final pathology；
- •Negative surgical margins ≥3 mm, including margins obtained after re-excision；
- •Unifocal lesion；
- •Absence of comedo necrosis；
- •Screen-detected disease without bloody nipple discharge or palpable mass；
- •Clinically node-negative disease；
- •Central pathology review by the participating institution required；
- •Ability to understand and willingness to sign written informed consent.
Exclusion Criteria
- •Known BRCA1, BRCA2, or TP53 germline mutation carriers (genetic testing not mandatory)；
- •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；
- •Pregnant or breastfeeding patients；
- •Estimated life expectancy ≤5 years；
- •Poor compliance or inability to adhere to study follow-up requirements.
Arms & Interventions
Radiotherapy Omission
Patients will undergo observation alone after breast-conserving surgery with regular clinical and imaging follow-up. Endocrine therapy is permitted according to institutional practice.
Intervention: Observation (Other)
Radiotherapy Omission
Patients will undergo observation alone after breast-conserving surgery with regular clinical and imaging follow-up. Endocrine therapy is permitted according to institutional practice.
Intervention: Endocrine Therapy (Optional) (Drug)
Outcomes
Primary Outcomes
Ipsilateral Breast Tumor Recurrence (IBTR)
Time Frame: 5 years
Defined as recurrence of invasive carcinoma or DCIS in the ipsilateral breast.
Secondary Outcomes
- 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)
- 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)
- Anxiety Assessment(5 years)
- Patient-Reported Outcomes(5 years)
Investigators
Xiaoli Yu
Professor
Fudan University