CPAP-assisted radiotherapy to lower heart and lung dose after breast-conserving surgery

Reducing Cardiac Radiation Dose in Continuous Positive Airway Pressure (CPAP) Assisted Radiotherapy in Breast Cancer: a Prospective Non-Randomized Clinical Trial

This tests whether wearing a CPAP breathing device during adjuvant radiotherapy can lower radiation exposure to the heart and lungs for women with early-stage (stage 1–3) breast cancer who had breast‑conserving surgery.

Quick facts

• Phase: PHASE2; PHASE3
• Study type: Interventional
• Enrollment: 53 (estimated)
• Ages: 40 Years to 80 Years
• Sex: Female
• Sponsor: Universitaire Ziekenhuizen KU Leuven (other)
• Drugs / interventions: chemotherapy, immunotherapy, radiation
• Locations: 1 site (Leuven)
• Trial ID: NCT07373782 on ClinicalTrials.gov

What this trial studies

This is a prospective, non-randomized study enrolling women after breast‑conserving surgery who need adjuvant radiotherapy (left‑sided cases with or without regional nodal irradiation, and right‑sided cases requiring regional nodal RT). Each participant receives an extra CT simulation with CPAP at 15 cm H2O (left‑sided patients generally with DIBH; right‑sided in free breathing; left patients unable to do DIBH evaluated in free breathing). Two radiotherapy plans (with and without CPAP) are created and compared dosimetrically, and treatment is delivered with CPAP if predefined dose reductions are met (≥0.5 Gy mean heart or CLB dose or ≥1 Gy mean lung dose). Patient comfort is recorded via surveys and the study examines how CPAP use could be implemented in daily radiotherapy practice.

Who should consider this trial

Good fit: Women aged 40–80 who have had breast‑conserving surgery and require adjuvant radiotherapy—especially left‑sided tumors or right‑sided cases needing regional nodal RT—who can tolerate CPAP and (when applicable) DIBH are the intended participants.

Not a fit: Patients unlikely to benefit include those whose treatment plans show no meaningful dosimetric reduction with CPAP, and those with contraindications to CPAP such as active bullous lung disease, pneumothorax, bypassed upper airway, cerebral spinal fluid leaks, or who cannot tolerate the device or DIBH.

Why it matters

Potential benefit: If successful, this approach could lower radiation doses to the heart and lungs and potentially reduce long-term cardiac and pulmonary side effects.

How similar studies have performed: Deep inspiration breath hold (DIBH) is an established method to reduce cardiac dose in left‑sided breast radiotherapy, while CPAP is a newer approach with small dosimetric studies suggesting potential benefit but limited large‑scale outcome data.

Eligibility criteria

Inclusion Criteria:

1. Voluntary written informed consent of the participant or their legally authorized representative has been obtained prior to any screening procedures
2. At least 40 years of age and 80 years or younger at the time of signing the Informed Consent Form (ICF)
3. Female patients
4. Patients that underwent breast conserving surgery (BCS)
5. Left-sided invasive BC / in situ carcinoma with indication for adjuvant RT (\<70 years old)
6. Left-sided invasive BC with indication for adjuvant locoregional RT (including RT of the regional lymph nodes) (70-80 years old)
7. Right-sided invasive BC with indication for adjuvant locoregional RT (including RT of the regional lymph nodes)
8. Prior chemotherapy allowed
9. Prior immunotherapy allowed
10. Prior / concomitant hormonal therapy allowed
11. Prior / concomitant HER2-targeted therapy allowed

Exclusion Criteria:

1. Patient has active bullous lung disease, bypassed upper airway, pneumothorax, cerebral spinal fluid leaks, abnormalities of the cribriform plate (contra-indications for the use of CPAP)
2. Patient has history of major head trauma and/or pneumocephalus (contra-indications for the use of CPAP)
3. Any disorder, which in the investigator's opinion might jeopardise participant's safety or compliance with the CIP.
4. Female who is pregnant, breast-feeding or intends to become pregnant (which is a contra-indication for RT in general)
5. Male BC patients
6. Patients that underwent mastectomy Patients whose initial tumor was located just beneath the skin (defined as being less than 28mm below the breast surface), indicating the need for an electron boost
7. Patients requiring RT boost on positive lymph nodes
8. Distant metastasis
9. Breast implants in situ
10. Right-sided in situ carcinoma
11. Right-sided invasive BC only requiring local adjuvant RT (without irradiation of the regional lymph nodes, because the presumed benefit on cardiac doses of local right-sided breast irradiation is assumed to be rather small because of the left anatomical position of the heart)
12. Bilateral BC
13. Concomitant use of chemotherapy during RT
14. Substantial comorbidities, incompatible with RT or CPAP use, estimated by the treating radiation oncologist
15. Insufficient arm mobility to perform comfortable arm positioning in radiation treatment position, evaluated by the treating radiation oncologist
16. Other active oncological disease / treatment with the exception of non-melanoma skin cancer
17. Previous RT with overlapping RT fields with actual target volume

Where this trial is running

Leuven

• UZ Leuven — Leuven, Belgium (RECRUITING)

Study contacts

• Study coordinator: Aline Van der Vorst, MD

Conditions: Breast Cancer Early Stage Breast Cancer, breast cancer, radiotherapy, cpap, continuous positive airway pressure, dosimetry, toxicity