Robustness Evaluation of Deep Inspiration Breath-Hold (DIBH) Plans in Internal Mammary Irradiation

NCT07498855 | Recruiting

• 1 other identifier: RJBC-DIBH
• Study Type: observational
• Target: 25
• Locations: 1 country
• Sites: 1

Brief Summary

This study is an investigator-initiated, single-arm, single-center, prospective, observational study. The hypothesis is that during the implementation of deep inspiration breath-hold (DIBH) radiotherapy plans in postoperative breast cancer patients receiving internal mammary irradiation, the actual target dose coverage and organ-at-risk (OARs) dose parameters remain within clinically acceptable ranges.

Conditions

Breast Cancer

Keywords

DIBH; regional nodal irradiation; Internal Mammary Irradiation; Robustness Evaluation; Postoperative breast cancer radiotherapy

Outcome Measures

Primary Outcomes (1)

• Target coverage of the Planning treatment volume (PTV)

  Target coverage of the PTV, defined by V95% (the percentage of the PTV volume receiving at least 95% of the prescribed dose).

  Upon completion of radiotherapy treatment planning, prior to the first fraction of treatment.

Secondary Outcomes (8)

• Additional dose-volume parameters of the PTV

  Upon completion of radiotherapy treatment planning, prior to the first fraction of treatment.

• Dose-volume parameters of the organs at risk (OARs)

  Upon completion of radiotherapy treatment planning, prior to the first fraction of treatment.

• Conformity Index (CI) of the PTV

  Upon completion of radiotherapy treatment planning, prior to the first fraction of treatment.

• Homogeneity Index (HI) of the PTV

  Upon completion of radiotherapy treatment planning, prior to the first fraction of treatment.

• Intra-fractional Error-PTV

  During each treatment fraction (daily, approximately 3-4 weeks per patient)

Other Outcomes (2)

• Cumulative Dose to PTV

  Across all treatment fractions (approximately 3-4 weeks per patient)

• Cumulative Dose to OARs

  Across all treatment fractions (approximately 3-4 weeks per patient)

Study Arms (3)

Arm1: 3 mm Gating Window Group

Participants will receive regional nodal and internal mammary irradiation using a hypofractionated regimen and the DIBH technique, with a respiratory gating tolerance of ±1.5 mm (a total of 3 mm).

Radiation: DIBH with 3mm Gating Window

Arm2: 2 mm Gating Window Group

Participants will receive regional nodal and internal mammary irradiation using a hypofractionated regimen and the DIBH technique, with a respiratory gating tolerance of ±1.0 mm (a total of 2 mm).

Radiation: DIBH with 2 mm Gating Window

Arm3: 1.5 mm Gating Window Group

Participants will receive regional nodal and internal mammary irradiation using a hypofractionated regimen and the DIBH technique, with a respiratory gating tolerance of ± 0.75 mm (a total of 1.5 mm).

Radiation: DIBH with 1.5 mm Gating Window

Interventions

DIBH with 3mm Gating Window RADIATION

The patient will receive moderately hypofractionated radiotherapy targeting the ipsilateral breast, supraclavicular and internal mammary nodes, and high-risk axillary region, with a prescribed dose of 40 Gy (RBE) /15Fx. IMRT, VMAT, or proton therapy will be chosen based on the radiation oncologist's judgment and patient preference. Respiratory gating tolerance is set at ±1.5 mm (3 mm total). Three simulated CT scans during DIBH will assess gating window positions: CT1: Breath-hold at the center of the gating window. CT2: Breath-hold at the upper edge, simulating maximum thoracic expansion. CT3: Breath-hold at the lower edge, simulating minimum thoracic expansion. Setup errors (intrafraction and interfraction) and respiratory waveforms monitored via Surface Guided Radiation Therapy（SGRT）systems will be recorded for analysis.

Arm1: 3 mm Gating Window Group

DIBH with 2 mm Gating Window RADIATION

The patient will receive moderately hypofractionated radiotherapy targeting the ipsilateral breast, supraclavicular and internal mammary nodes, and high-risk axillary region, with a prescribed dose of 40 Gy (RBE) /15Fx. IMRT, VMAT, or proton therapy will be chosen based on the radiation oncologist's judgment and patient preference. Respiratory gating tolerance is set at ±1 mm (2 mm total). Three simulated CT scans during DIBH will assess gating window positions: CT1: Breath-hold at the center of the gating window. CT2: Breath-hold at the upper edge, simulating maximum thoracic expansion. CT3: Breath-hold at the lower edge, simulating minimum thoracic expansion. Setup errors (intrafraction and interfraction) and respiratory waveforms monitored via SGRT systems will be recorded for analysis.

Arm2: 2 mm Gating Window Group

DIBH with 1.5 mm Gating Window RADIATION

The patient will receive moderately hypofractionated radiotherapy targeting the ipsilateral breast, supraclavicular and internal mammary nodes, and high-risk axillary region, with a prescribed dose of 40 Gy (RBE) /15Fx. IMRT, VMAT, or proton therapy will be chosen based on the radiation oncologist's judgment and patient preference. Respiratory gating tolerance is set at ± 0.75 mm (1.5 mm total). Three simulated CT scans during DIBH will assess gating window positions: CT1: Breath-hold at the center of the gating window. CT2: Breath-hold at the upper edge, simulating maximum thoracic expansion. CT3: Breath-hold at the lower edge, simulating minimum thoracic expansion. Setup errors (intrafraction and interfraction) and respiratory waveforms monitored via SGRT systems will be recorded for analysis.

Arm3: 1.5 mm Gating Window Group

Eligibility Criteria

• Age: 18 Years+
• Sex: female
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Female patients aged ≥18 years with left-sided postoperative invasive breast cancer scheduled for DIBH radiotherapy targeting the internal mammary and regional lymph nodes at Ruijin Hospital, Shanghai JiaoTong University School of Medicine. The study will recruit a total of 25 participants, divided into three cohorts based on different respiratory gating tolerances (3 mm, 2 mm, and 1.5 mm).

You may qualify if:

• Provide a signed and dated informed consent form (ICF) before the initiation of any trial-specific procedures.
• Female patients aged ≥ 18 years.
• Histologically confirmed invasive breast cancer.
• Have received breast-conserving surgery or mastectomy with axillary staging, including sentinel lymph node biopsy and/or axillary lymph node dissection.
• Able to hold breath for more than 30 seconds after deep inspiration.
• Planned to receive postoperative radiotherapy targeting regional lymph nodes, including the internal mammary nodes, under DIBH conditions.
• Planned to undergo moderate hypofractionated radiotherapy.
• Karnofsky Performance Status (KPS) score ≥ 80.
• The estimated life expectancy of greater than 5 years .
• Sufficient wound healing from surgery, with no signs of active infection at the intended radiation site.

You may not qualify if:

• Pregnant or breastfeeding women.
• Presence of any severe, uncontrolled comorbidity or medical condition that, in the investigator's judgment, would render the participant unsuitable for the study, compromise protocol compliance, or confound the interpretation of study results.
• Unable to understand or comply with breath-hold training instructions.
• Right-sided breast cancer.

Sponsors & Collaborators

• Ruijin Hospital: lead

Study Sites (1)

Ruijin Hospital, Shanghai Jiaotong University School of Medicine

Shanghai, Shanghai Municipality, 200025, China

RECRUITING

MeSH Terms

Conditions

Breast Neoplasms

Condition Hierarchy (Ancestors)

Neoplasms by Site; Neoplasms; Breast Diseases; Skin Diseases; Skin and Connective Tissue Diseases

Central Study Contacts

Lu Cao, PhD

CONTACT

+86-021-64370045; cl11879@rjh.com.cn

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor

Study Record Dates

• First Submitted: January 16, 2026
• First Posted: March 27, 2026
• Study Start: October 1, 2025
• Primary Completion (Estimated): December 31, 2026
• Study Completion (Estimated): May 31, 2027
• Last Updated: March 27, 2026

Record last verified: 2026-03

Data Sharing

• IPD Sharing: Will not share

Locations

CN (1)