Breast Cancer
Conditions
Brief summary
Radiotherapy (RT) has a major curative role in women with early breast cancer, and is recommended routinely after lumpectomy and selectively after mastectomy. It has contributed to a halving of breast cancer mortality in the UK over the last 2 decades despite ever-rising cancer incidence. RT in women with left-sided tumours often exposes the underlying heart to a damaging dose. The heart is very sensitive to RT, and there were 1-2 deaths from heart disease for every 100 breast cancer patients treated during the 1960s-70s. The situation has improved in recent years, but standard RT techniques still deliver significant radiation doses to heart tissue. Two potentially simple techniques reduce heart dose. In one, women are taught to breathe in deeply and to hold their breath for about 20 seconds while RT is given. The downward movement of the diaphragm pulls the heart away from the RT beam. In the other technique, women lie on their fronts, instead of on their backs as they normally do for breast RT. In this position, the breast falls away from the rib cage and reduces exposure of the heart. Neither technique is routinely available to women receiving breast RT in the UK for reasons that this research aims to address. The investigators need to: 1) confirm that patient position can be reproduced with millimetre precision every day using these techniques, 2) minimise costs of equipment, time and personnel required to support such techniques, 3) select the most appropriate technique for different patients and 4) train staff in centres across the UK to deliver techniques safely and effectively. By addressing all of these issues, the study aims ultimately to make heart-sparing RT available to all UK women that might benefit from treatment, thereby significantly reducing the burden of heart disease in breast cancer survivors.
Interventions
PROCEDUREVoluntary deep-inspiratory breath hold
Patients undergoing scanning in v\_DIBH will be positioned supine with arms extended on a MedTec breast board. They will be monitored visually on screen and will be given a buzzer to press when they have taken a breath. CT images will be obtained during DIBH. If the patient needs to release their breath, they will be asked to press the buzzer a second time. Patients will be closely monitored by radiographers via CCTV.
PROCEDUREActive-breathing-controlled deep-inspiratory breathhold
Patients undergoing scanning in ABC\_DIBH will be positioned supine with arms extended on a MedTec breast board to which an activated-breathing control device (Elekta, Crawley, UK) has been attached. They will breathe through the device. During ABC\_DIBH, CT images will be obtained.
PROCEDUREProne treatment
Patients undergoing scanning in a prone position will lie on a customised prone treatment platform. CT images will be acquired under free-breathing conditions.
Sponsors
Royal Marsden NHS Foundation Trust
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
FEMALE
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Complete microscopic excision of early stage invasive ductal or lobular carcinoma (pT1-3b N0-1 M0) of the left breast following breast conservation surgery or mastectomy. * Recommendation for whole breast (groups A and B) or chest wall (Group A only) radiotherapy (with or without tumour bed boost) * Age ≥18 * Performance status ≤1 * Patients able to tolerate breath-hold
Exclusion criteria
* Requirement for nodal irradiation * Patients with micro- or macro-scopic disease on sentinel node biopsy who have not undergone completion axillary node clearance * Previous radiotherapy to any region above the diaphragm
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Interfraction reproducibility of chest wall position (group A) | End of radiotherapy (3-4 weeks) | The position of ipsilateral chest wall will be compared between the digitally reconstructed radiographs (derived from the planning CT) and the on-treatment electronic portal images and mean daily displacements calculated. |
| Difference in mean left anterior descending coronary artery (LAD) mean normal tissue dose (NTDmean) (group B) | End of radiotherapy (3-4 weeks) | Using dose-volume histograms (DVHs) based on the planning scan and on-treatment CBCT imaging, mean LAD NTDmean will be compared for ABC\_DIBH versus prone positioning. |
Secondary
| Measure | Time frame |
|---|---|
| Comparison of individual patient heart NTDmean differences by anatomical factors (group B) | End of radiotherapy (3-4 weeks) |
| Difference in mean normal tissue doses (NTDmean) to heart, ipsilateral and whole lungs (group B) | End of radiotherapy (3-4 weeks) |
| Difference in volumes of chest wall receiving 20Gy (Groups A and B) | End of radiotherapy (3-4 weeks) |
| Difference in NTDmean for heart, LAD, ipsilateral and whole lungs (group A) | End of radiotherapy (3-4 weeks) |
| Interfraction reproducibility of tumour bed position (groups A and B) | End of radiotherapy (3-4 weeks) |
| Time and equipment costs (groups A and B) | End of study (2 years) |
| Patient and radiographer satisfaction with positioning technique (groups A and B) | Weekly questionnaire |
| Interfraction reproducibility of chest wall position (groups A and B) | End of radiotherapy (3-4 weeks) |
| Comparison of standard deviation in mean LAD NTDmean over a treatment course (group B) | End of radiotherapy (3-4 weeks) |
Countries
United Kingdom
Outcome results
None listed