CClinicalTrials.gg
RecruitingNCT07762924Updated Aug 13, 2026

Omission of Adjuvant Radiotherapy in Young Low-Risk Ductal Carcinoma In Situ Following Breast-Conserving Surgery

A Phase 2 interventional study of Observation and Endocrine Therapy (Optional) in Ductal Carcinoma In Situ, DCIS, sponsored by Fudan University. Recruiting at 1 site in China. Open to female participants aged Up to 40 Years. Per ClinicalTrials.gov, last updated 2026-08-13.

Sponsored by Fudan University · Phase 2, Interventional, and Treatment

Phase
Phase 2
Study type
Interventional
Enrollment
234
Allocation
Not applicable
Ages
Up to 40 Years
Sex
Female
01

Study 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).

02

Conditions studied

  • Ductal Carcinoma In Situ, DCIS
03

Who can participate

Ages eligible
Up to 40 Years
Sexes eligible
Female
Accepts healthy volunteers
No

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 ≤1 cm on final pathology;
  4. Negative surgical margins ≥3 mm, including margins obtained after re-excision;
  5. Unifocal lesion;
  6. Absence of comedo necrosis;
  7. Screen-detected disease without bloody nipple discharge or palpable mass;
  8. Clinically node-negative disease;
  9. Central pathology review by the participating institution required;
  10. Ability to understand and willingness to sign written informed consent.

Exclusion criteria

Exclusion Criteria:

  1. Known BRCA1, BRCA2, or TP53 germline mutation carriers (genetic testing not mandatory);
  2. Bilateral breast cancer or prior contralateral breast cancer;
  3. Severe uncontrolled comorbidities, including significant cardiac, pulmonary, hepatic, renal, hematologic, or psychiatric disorders;
  4. History of other malignancies, including thyroid cancer, except adequately treated basal cell carcinoma of the skin or cervical carcinoma in situ;
  5. Pregnant or breastfeeding patients;
  6. Estimated life expectancy ≤5 years;
  7. Poor compliance or inability to adhere to study follow-up requirements.
04

Study design

Phase
Phase 2
Primary purpose
Treatment
Allocation
Not applicable
Intervention model
Single group
Masking
None (open label)
Enrollment
234 participants (estimated)

Study arms

  • Experimental
    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.

    Other: Observation · Drug: Endocrine Therapy (Optional)

Interventions

  • OtherObservation

    No postoperative radiotherapy will be administered. Patients will receive close surveillance after surgery.

  • DrugEndocrine Therapy (Optional)

    Adjuvant endocrine therapy may be administered according to physician discretion and patient preference.

05

What researchers measure

Primary outcomes

  1. Ipsilateral Breast Tumor Recurrence (IBTR)

    Defined as recurrence of invasive carcinoma or DCIS in the ipsilateral breast.

    Time frame: 5 years

Secondary outcomes

  1. Local-Regional Recurrence (LRR)

    Defined as recurrence in the ipsilateral breast, chest wall, supraclavicular region, axilla, or internal mammary region.

    Time frame: 5 years

  2. Breast Cancer-Specific Survival (BCSS)

    Defined as time from study enrollment to death due to breast cancer.

    Time frame: 5 years

  3. Overall Survival (OS)

    Defined as time from study enrollment to death from any cause.

    Time frame: 5 years

  4. Distant Metastasis-Free Survival (DMFS)

    Distant Metastasis defined as recurrence outside local-regional sites.

    Time frame: 5 years

  5. Contralateral Breast Cancer Events

    Defined as participants diagnosed with a new primary breast cancer in the contralateral breast. Diagnosis will be confirmed by pathological examination.

    Time frame: 5 years

  6. Mastectomy-Free Survival

    Defined as participants who are alive and have not undergone mastectomy of the treated breast after initiation of study treatment.

    Time frame: 5 years

  7. Second Primary Malignancies

    Defined as participants diagnosed with a new primary malignancy, excluding recurrence or metastasis of the index breast cancer.

    Time frame: 5 years

  8. Quality-of-Life Assessed by the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (EORTC QLQ-C30)

    Global health quality of life is assessed using the EORTC QLQ-C30. Scores are transformed to a 0-100 scale, with higher scores indicating better global health status and quality of life. Change from baseline will be evaluated during follow-up.

    Time frame: 5 years

  9. 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)

    Breast cancer-specific symptom burden is assessed using the EORTC QLQ-BR23. Scores are transformed to a 0-100 scale. Change from baseline will be evaluated during follow-up.

    Time frame: 5 years

  10. Anxiety Assessment

    Change from baseline in anxiety symptoms assessed using a validated patient-reported anxiety assessment instrument.

    Time frame: 5 years

  11. Patient-Reported Outcomes

    Change from Baseline in Patient-reported Treatment-related Symptoms Assessed by PRO-CTCAE.

    Time frame: 5 years

Other outcomes

  1. Tumor-Infiltrating CD8-Positive T-Cell Density

    Density of tumor-infiltrating CD8-positive T cells in pretreatment tumor tissue, assessed by IHC or mIF.

    Time frame: Baseline

  2. Tumor PD-L1 Expression

    PD-L1 expression in pretreatment tumor tissue assessed by IHC and quantified using the Combined Positive Score (CPS).

    Time frame: Baseline

06

Study locations

1 of 1 sites recruiting
  • Fudan University Shanghai Cancer Center
    Shanghai, 200032, China
    Recruiting
07

Registry details

Key details

Study ID
NCT07762924
Lead sponsor
Fudan University
Responsible party
Xiaoli Yu (Professor, Fudan University) — Principal investigator
First posted
Aug 13, 2026
Start date
Sep 1, 2026 (estimated)
Primary completion
Feb 2032 (estimated)
Completion
Feb 2037 (estimated)
Last update
Aug 13, 2026

Study contacts

Xiaoli Yu
Contact
xiaoliyu@fudan.edu.cn
+86-021-64175590
Jin Meng
Contact
jinmeng@fudan.edu.cn
+86 18121299532

Oversight

FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

Interested in this study?

Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.

Contact study team

Follow this study

Get an email when the registry record changes — status, dates, results — or when someone posts here.

Sign in to follow

Discussion

Questions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.

Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.

Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.

Start the discussion