Breast cancer patients with ipsilateral diaphragm paralysis: practical breast radiotherapy using continuous positive airway pressure-assisted breathing to spare normal organs-sparing

Sep 29, 2026

Purpose: To describe organs at risk (OARs)-sparing breast cancer radiotherapy for patients with ipsilateral diaphragm paralysis using continuously positive airway pressure (CPAP) and supine tangential RT fields. Material and method: Free-breathing plans showed elevated ipsilateral diaphragm with organ displacement; CPAP-based CT simulation created supine tangential plans. Results: Compared with free breathing, CPAP inflated lungs and shifted paralyzed diaphragm, liver, heart, and intestine away, yielding marked reductions in liver, heart, and intestine dose. Conclusion: CPAP is an effective, practical technique for OARs-sparing breast RT in this patient group.

LanguageEnglish

CategoryHealthcare

FormatPDF

Pages4

Reading Time10 min

AccessFree to download

Introduction

Adjuvant breast radiotherapy and organ-at-risk sparing

Deep inspiration breath-hold limitations with diaphragm paralysis

Role of CPAP-assisted breathing in radiotherapy

Technical Innovations & Patient Support in Radiation Oncology 37 (2026) 100363 Contents lists available at ScienceDirect Technical Innovations & Patient Support in Radiation Oncology journal [homepage:](homepage: www.sciencedirect.com/journal/technical-innovations-and)[ www.sciencedirect.com/journal/technical-innovations-and](homepage: www.sciencedirect.com/journal/technical-innovations-and)patient-support-in-radiation-oncology | Case reports and case series
Breast cancer patients with ipsilateral diaphragm paralysis: practical breast radiotherapy using continuous positive airway pressure-assisted breathing to spare normal organs | | | | | --- | --- | --- | --- | | Whoon Jong Kila,b,c,* , Wyatt Smith a , David Cousinsa
a Radiation Oncology, UPMC Hillman Cancer Center, Williamsport, PA, USA
b Department of Radiation Oncology, Walter Reed National Millitary Medical Center, Bethesda, MD, USAc Department of Radiation Oncology, Univeresity of Pittsburgh School of Medicine, Pittsburgh, PA, USA | | | | | A R T I C L E I N F O | | A B S T R A C T | | | Keywords:
Breast cancer
Ipsilateral diaphragm paralysis Normal organs-sparing
CPAP
Radiotherapy | | Purpose: To describe organs at risk (OARs)-sparing breast cancer (BC) radiotherapy (RT) for patients with ipsilateral (Ipsi-diaphragm) paralysis using continuously positive airway pressure (CPAP) and supine tangential RTfield.
Material and method: Breast RT plans with free-breathing (FB) for a patient with right-sided BC (patient1) and another patient with left-sided BC (patient2) showed an elevated Ipsi-diaphragm and displaced portions of liver (patient1) and the heart and intestine (patient2) into supine tangential RT-field. Although both patients denied cardiopulmonary symptoms, their elevated diaphragm, liver, intestine and the heart were unchanged with deepinspiration breath hold (DIBH) while contralateral diaphragm moved caudally suggesting clinical diagnosis of Ipsi-diaphragm paralysis. Subsequently, patients underwent CT-sim under CPAP to create supine tangential breast RT plan.
Result: Compared with FB, CPAP inflated lungs and moved both patients paralyzed diaphragm, liver, heart, and intestine caudally and displaced these OARs away from breast RT-field. The liver volume within right supine tangential RT-fields in patient1 was 163 cc with FB versus 12 cc with CPAP (93 % reduction). The heart and intestine were completely outside the left supine tangential RT-field with CPAP in patient2. For dosimetric comparison, supine tangential RT-fields for breast-only RT were used with prescription of 40 Gy in 15 fractionson each patients’ CT-sim with FB and CPAP, respectively. Compared with FB, CPAP reduced liver volume receiving ≥ 30 Gy by 94 %(FB:140 vs CPAP:8 cc) in patient1 and mean dose to the heart by 67 %(FB:2.7 vs CPAP:0.9 Gy) and left anterior descending artery by 84 %(FB:25 vs CPAP:3.9 Gy), maximum dose to the intestine by 90 %(FB:40.6 vs CPAP:4.4 Gy).
Conclusion: BC patients with Ipsi-diaphragm paralysis, CPAP provided an effective and practical technique for OARs-sparing breast RT. | | Introduction Adjuvant radiotherapy (RT) is an important part of breast cancer (BC) treatment and has significantly improved local tumor control and survival in patients with BC [1,2]. With improved patients’ survival, there has been growing interest in lowering radiation dose to normal organs within or near breast RT field (OARs: the heart and lung) to minimize the risk of RT-related toxicities and non-BC related mortality [3–6]. Deep inspiration breath-hold (DIBH) is a commonly adopted technique in radiation centers for breast RT [6]. When patients take deep inspiration, their diaphragm contracts, flattens and moves caudally to create a negative pressure in the thoracic cavity, which allows air to flow into the lung, inflating thorax, increasing lung volume and displacing the heart away from the chest wall compared with free breathing (FB). A

FAQs

What is the purpose of using CPAP-assisted breathing in breast radiotherapy for patients with ipsilateral diaphragm paralysis?

The purpose is to achieve organs-at-risk (OARs)-sparing breast cancer radiotherapy by displacing critical organs away from the treatment field using CPAP and supine tangential planning.

How did free-breathing and deep inspiration breath-hold help identify ipsilateral diaphragm paralysis in the reported patients?

Elevated ipsilateral diaphragm with displacement of nearby organs was observed on free-breathing planning, while the elevated diaphragm and displaced organs were unchanged with deep inspiration breath-hold, supporting a diagnosis of ipsilateral diaphragm paralysis.

What dosimetric advantages did CPAP provide compared with free breathing?

Compared with free breathing, CPAP reduced liver volume receiving ≥30 Gy by 94% in the right-sided case, lowered mean heart dose by 67%, reduced left anterior descending artery dose by 84%, and decreased maximum intestine dose by 90%.

Sep 29, 2026

Uploaded by Lucas Martin