Omission of Adjuvant Radiotherapy in Low- and Intermediate-Risk Ductal Carcinoma In Situ After Breast-Conserving Surgery

Official record

Identifier

NCT07762885

Recruiting locations

country

China

Interventions studied

Adjuvant Radiotherapytamoxifen

Lead sponsor

Fudan University

Target enrolment

636 participants

Study type

INTERVENTIONAL

Phase

Phase 3

Status

Recruiting

First posted

Aug 13, 2026

Last updated on the registry

Aug 13, 2026

Age

40 Years

Sex

FEMALE

Study contact

The official record lists a study contact. Contact details are published there and are intentionally not copied to this page.

Eligibility criteria

Reproduced verbatim from the official record. Eligibility is decided by the study team, never by this page.

Inclusion Criteria:

1. Female patients aged ≥40 years；
2. Histologically confirmed low- or intermediate-grade ductal carcinoma in situ (DCIS) without invasive carcinoma, including incidental DCIS identified within benign breast lesions；
3. Tumor size ≤2.5 cm on final pathology；
4. Negative surgical margins ≥3 mm, including margins obtained after re-excision；
5. Estrogen receptor-positive disease (ER ≥10%) with planned endocrine therapy using tamoxifen；
6. Unifocal lesion；
7. Absence of comedo necrosis；
8. Screen-detected disease without bloody nipple discharge or palpable mass；
9. Clinically node-negative disease；
10. Patients randomized to the radiotherapy arm must initiate radiotherapy within 3 months after surgery；
11. Central pathology review by the participating institution required；
12. Ability to understand and willingness to sign written informed consent.

Exclusion Criteria:

1. Known BRCA1 or BRCA2 germline mutation carriers (genetic testing not mandatory)；
2. Contraindications to radiotherapy, including active connective tissue disease；
3. Active infection requiring systemic treatment；
4. Bilateral breast cancer or prior contralateral breast cancer；
5. Severe uncontrolled comorbidities, including significant cardiac, pulmonary, hepatic, renal, hematologic, or psychiatric disorders；
6. History of other malignancies, including thyroid cancer, except adequately treated basal cell carcinoma of the skin or cervical carcinoma in situ；
7. Prior thoracic radiotherapy；
8. Pregnant or breastfeeding patients；
9. Estimated life expectancy ≤5 years；
10. Poor compliance or inability to adhere to study follow-up requirements.

Indexed under

Breast Cancer