De-escalation of RNI in Breast Cancer Patients With pN0 After Neoadjuvant Therapy (OMIT-RNI)

July 21, 2026 updated by: Aya Ahmed Sayed

Prospective Comparative Study of Response-Adapted De-escalation of Regional Nodal Irradiation in Initially Node Positive Breast Cancer Patients With Pathological Nodal Complete Response After Neoadjuvant Therapy

Prospective Comparative Study of Response-Adapted De-escalation of Regional Nodal Irradiation in Initially Node Positive Breast Cancer Patients with Pathological Nodal Complete Response After Neoadjuvant Therapy

Study Overview

Status

Not yet recruiting

Conditions

Intervention / Treatment

Detailed Description

This prospective, randomized comparative study aims to evaluate the clinical outcomes and safety of response-adapted de-escalation of Regional Nodal Irradiation (RNI) in initially node-positive (cN1) breast cancer patients who achieved a pathological nodal complete response (pCR) following neoadjuvant systemic therapy. Patients will be randomized into two arms: Arm A (Experimental Arm) which omits regional nodal irradiation, and Arm B (Control Arm) which receives standard regional nodal irradiation.

Study Type

Interventional

Enrollment (Estimated)

100

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Female patients >= 18 years old.
  • Histologically confirmed invasive breast cancer, cT1-3 N1M0 according to the 8th AJCC edition.
  • Biopsy-proven cN1 disease at diagnosis.
  • Completion of standard neoadjuvant systemic therapy.
  • Surgical treatment of breast and axilla.
  • Pathologically confirmed ypN0 status.
  • ECOG performance status 0-2.
  • Suitable for adjuvant radiotherapy.
  • Signed informed consent.

Exclusion Criteria:

  • Metastatic disease (M1).
  • Prior thoracic irradiation.
  • Pregnancy or lactation.
  • Severe uncontrolled comorbid illness.
  • Any contraindication to radiotherapy.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Arm A: Experimental Arm
Patients will receive whole breast irradiation (WBI) following breast-conserving surgery or chest wall irradiation (CWI) following mastectomy, without regional nodal irradiation (RNI).
Radiation: Adjuvant Radiotherapy
Adjuvant radiation therapy will be delivered using Three-Dimensional Conformal Radiotherapy (3DCRT) or Intensity-Modulated Radiotherapy (IMRT). Standard institutional contouring and dosing protocols will be applied to the target volumes (whole breast or chest wall, with or without regional nodal regions) based on the randomized arm assignment.
Active Comparator: Arm B:Control Arm
Patients will receive standard whole breast irradiation (WBI) or chest wall irradiation (CWI) combined with standard regional nodal irradiation (RNI) according to institutional protocol and current international guidelines.
Radiation: Adjuvant Radiotherapy
Adjuvant radiation therapy will be delivered using Three-Dimensional Conformal Radiotherapy (3DCRT) or Intensity-Modulated Radiotherapy (IMRT). Standard institutional contouring and dosing protocols will be applied to the target volumes (whole breast or chest wall, with or without regional nodal regions) based on the randomized arm assignment.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Locoregional Recurrence (LRR) Rate
Time Frame: 3 years
The percentage of patients who experience tumor recurrence in the ipsilateral breast/chest wall or regional lymph nodes (axillary, supraclavicular, or internal mammary lymph nodes) during the follow-up period
3 years

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Invasive Disease-Free Survival (iDFS)
Time Frame: 5 years
The time from randomization to the date of first documentation of invasive local, regional, or distant recurrence, contralateral invasive breast cancer, or death from any cause.
5 years
Radiation Toxicity
Time Frame: From start of radiotherapy up to 1 year post-treatment
Incidence of acute and late radiation toxicities, including lymphedema, radiation pneumonitis, cardiac toxicity, brachial plexopathy, and shoulder dysfunction, graded according to the Common Terminology Criteria for Adverse Events (CTCAE) version 5.0.
From start of radiotherapy up to 1 year post-treatment
Overall Survival (OS)
Time Frame: 5 years
The time from randomization to the date of death from any cause.
5 years

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Aya Ahmed Sayed

Investigators

  • Study Chair: Mohamed Soliman, Sohag University

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

June 1, 2026

Primary Completion (Estimated)

June 1, 2028

Study Completion (Estimated)

June 1, 2029

Study Registration Dates

First Submitted

July 19, 2026

First Submitted That Met QC Criteria

July 21, 2026

First Posted (Actual)

July 24, 2026

Study Record Updates

Last Update Posted (Actual)

July 24, 2026

Last Update Submitted That Met QC Criteria

July 21, 2026

Last Verified

July 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • Soh-Med--26-7-1MD

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

IPD Plan Description

Individual participant data will not be shared outside the study investigators.

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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