An observational study in Breast Cancer, sponsored by Amsterdam UMC, location VUmc. Completed at 1 site in Netherlands. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-07-16.
Sponsored by Amsterdam UMC, location VUmc · Observational
Postoperative radiotherapy is for the majority of breast cancer patients the standard of care. During postoperative radiotherapy, unexpected dosimetric deviations can occur due to breast contour changes resulting from resorption of postoperative breast or chest wall seroma/hematoma, oedema either postoperatively or during irradiation, or arm/body positioning variation. In approximately 10% of cases, repositioning after setup imaging is not sufficient, and offline plan adaptation is required. When a new treatment planning is required in the standard offline workflow this will take in general 2 days. By using an online adaptive workflow with a daily treatment planning this delay and extra work caused by offline plan adaptation can be omitted. The aim of this study is to translate the offline adaptive workflow to an online adaptive workflow, and investigate the experiences of patients who have been treated with online adaptive radiotherapy for breast cancer (BREAST-ART).
In this single-arm prospective BREAST-ART study breast cancer patients with an indication for postoperative radiotherapy will be treated according to the Dutch and institutional guidelines. Target volumes will be the whole breast, chest wall, axillary levels, tumor bed boost and partial breast irradiation on the right side and left side with a deep inspiration breath hold technique. Robust templates are developed for offline and online treatment planning with an IMRT tangential multiple-beam setup. A simulation of the online adaptive workflow is performed in breast cancer patients already treated on the Ethos-linac with the standard offline adaptive workflow. Patients will be treated following the online adaptive workflow delivered on the Ethos-Linac. Patient experience will be evaluated using an in-house developed questionnaires after the first and last fraction, scoring treatment satisfaction on a 4-point Likert scale. Furthermore, all dosimetric data, volume details, DICOM images and the time spend on all parts of the online adaptive workflow will be evaluated.
12,544 studies on the registry are indexed under Breast Neoplasms; 2,892 are open to participants now.
This study's enrollment of 50 is below the median of 184 across 2,642 observational studies indexed under Breast Neoplasms.
Browse Breast Neoplasms studies →Amsterdam UMC, location VUmc is the lead sponsor of 302 studies on the registry; 84 are open to participants now.
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Breast cancer patients undergoing postoperative radiation treatment.
Exclusion Criteria:
Breast cancer patients treated with postoperative radiotherapy in an online adaptive workflow on Ethos.
Radiation: Online adaptive radiotherapy
Postoperative radiotherapy will be indicated conform the standard medical care and guidelines. The radiation is delivered with online adaptive radiotherapy performed on the Ethos. This technique will be evaluated.
Time spend on the online adaptive workflow
All separate parts of the online adaptive workflow will be registered in minutes, starting when the patients enters the room of the radiation machine until the patient leaves the room.
Time frame: 30 minutes
Patient experience
Patient experience is measured using an in-house designed short study questionnaire after the first and the last radiation fraction. The questionnaires is on a 4-point Likert scale with a lowest score for discomfort and the highest score appears for good comfort.
Time frame: 10 minutes
Dosimetric data
The dosimetric data of the standard offline treatment plan (reference plan), scheduled plan and the online adapted treatment plan (adapted plan) will be compared.
Time frame: 1 week
DICOM images
DICOM images of the standard offline treatment plan (reference plan), scheduled plan and the online adapted treatment plan (adapted plan) will be compared.
Time frame: 1 week
Volumes
Target volumes of clinical target volume (CTV), planning target volume (PTV), coverage of CTV and PTV will be registred in cubic centimetres.
Time frame: 1 week
Number of monitor units (MU).
The number of monitor units (MU) will be compared between the reference treatment plan, scheduled plan and adapted treatment plan.
Time frame: 1 week
Radiation associated toxicity
Toxicity will be assessed by the Common Terminology Criteria Adverse Events version 5.0.
Time frame: Baseline, 1 month and 3 months after radiotherapy
Plan to share: No
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This study is completed, as verified in Jul 2026. You cannot join it, but the record below documents what was studied.
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Amsterdam UMC, location VUmc