Pelvic and Para-aortic Lymph Node Metastases
Conditions
Keywords
pelvic, lymph node, para-aortic
Brief summary
In this study, the investigators want to investigate whether online-adapted radiotherapy using a special magnetic resonance imaging (MRI) simulator and computed tomography (CT)-guided radiation therapy, is feasible and offers advantages for the treatment of pelvic lymph node metastases.
Detailed description
MR-guided online adaptive radiotherapy has been implemented recently using MR-linac technology, where MR-imaging is combined with linac technology in hybrid systems. These systems offer MR imaging for online adaptive radiotherapy (RT) within the treatment room and with the patient in treatment position. Despite results regarding technical and clinical feasibility being promising, the high costs of MR-linacs systems and the high demands for staffing resources of MR-linacs are limiting a boarder implementation of this technology. At the Department of Radiation Oncology, University Hospital Zurich, MRI-simulations for RT planning using a dedicated scanner have been performed since 2023. The investigators have developed and implemented an MRI-only RT planning workflow followed by RT delivered at a CBCT-guided, conventional linac. The aim to expand the MRI-only workflow to online adaptive RT. This study will investigate the feasibility of MRI-guided, online adaptive SBRT for pelvic and para-aortic lymph node metastases using a dedicated MR simulator and treatment delivery using conventional CBCT-linac technology.
Interventions
RADIATIONMagnetic resonance Imaging-guided online adaptive radiotherapy
On each day of treatment, a new MRI scan in the treatment position will be acquired using the dedicated MR simulator, co-registered with the original one. The original target and organ at risk (OAR) contours will be propagated to the new image set using rigid and deformable image registration. The contours will be adapted to changes detected with MRI of the day. The original SBRT treatment plan will be adapted to the changed and hence adapted anatomy of targets and OARs by plan optimization. Dose calculation will be performed on the newly generated synthetic CT (preferred) or, if there is a contra-indication for synthetic CT, on the original image.
Sponsors
University of Zurich
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Intra-pelvic and para-aortic lymph node metastases from a histologically confirmed malignancy; * Indication for SBRT based on a multidisciplinary tumor board recommendation and / or clinical practice guideline; * Intra-pelvic and para-aortic lymph node metastases confirmed by imaging and amenable for SBRT
Exclusion criteria
* Large body size that would not fit the MRI-simulator bore; * Contraindications for MRI including but not limited to * electronic devices such as pacemakers, defibrillators, deep brain stimulators, cochlear implants that are labeled as MR unsafe. Electronic devices labeled as MR safe or MR conditional are not a contraindication; * metallic foreign body in the eye or aneurysm clips in the brain; * severe claustrophobia; * hip prosthesis that are labeled as MR unsafe; * More than 5 pelvic lymph node metastasis * Previous radiation therapy directly overlapping with SBRT in this study and leading to exceeding tolerance of OARs; * History of Crohn's disease, ulcerative colitis
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Rate of successfully delivered fractions | during treatment, 1-2 weeks | Feasibility is measured as a successful delivery of an MRI-adapted plan using CBCT image-guidance in another room in 90% of the SBRT fractions. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Average improvement of coverage of planning target volume | During treatment, 1-2 weeks | Dosimetric advantage is defined as \>5% improvement in coverage of the planning target volume (PTV) or \>5% better sparing of one of the organs at risk (bowel, sigma , rectum, bladder). |
| Adverse Events | during SBRT, 3 months and 24 months of follow-up | Common Terminology Criteria for Adverse Events (CTCAE), version 5.0 |
Countries
Switzerland
Outcome results
None listed