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Adaptive MR-guided SBRT for Localized Prostate Cancer

Feasibility Trial of Individualized Daily Dose Adaptation for Localized Prostate Cancer by Online MR-guided SBRT

Status
Not yet recruiting
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT04571762
Enrollment
12
Registered
2020-10-01
Start date
2024-09-30
Completion date
2026-05-30
Last updated
2024-05-23

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Prostate Cancer

Keywords

SBRT, MR-Linac, Adaptive radiotherapy, Prostate cancer

Brief summary

The purpose of this study is to evaluate a technical feasibility of MR-guided SBRT fraction dose adaptation for low-risk, intermediate-risk and low-volume metastatic prostate cancer. .

Detailed description

Hypofractionated SBRT to 36.25 Gy in 5 fractions (fraction dose 7.25 Gy) for low- and intermediate risk prostate cancer is standard of care. Using higher fraction doses that might be beneficial for disease control is not safe in all patients, unless adaptive treatment is performed. In this clinical trial the feasibility of online MR-guided SBRT fraction dose adaptation (between 7 and 8 Gy) for prostate cancer will be investigated. A fraction dose to the planning target volume (PTV) will be adapted to organs-at-risk (OAR) geometry (position, shape and volume) on online planning MRI scans of the treatment day (geometry-of-the-day). Thus the investigators hope to maximize treatment individualization.

Interventions

RADIATIONStereotactic Body Radiation Therapy (SBRT)

SBRT (a fraction dose adapted to the OAR geometry-of-the-day, 5 fractions) performed on the MR-Linac

Sponsors

University of Zurich
Lead SponsorOTHER

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
MALE
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* Written informed consent according to Swiss law and ICH/GCP regulations before any trial specific procedures; * Males; * Histologically confirmed adenocarcinoma of the prostate; * Low (Grade group 1 \[Gleason score ≤6\], clinical stage T1-2a N0 M0, and PSA \< 10 ng/ml) and intermediate (Grade group 2-3 \[Gleason score 7\], clinical stage T2b-2c N0 M0, PSA 10-20 ng/ml) risk prostate cancer with indications for SBRT with curative intent; * Newly diagnosed low-volume metastatic prostate cancer with indications for SBRT, in whom metastatic disease was confirmed on a bone scintigraphic scan and soft-tissue imaging done within 3 months of starting androgen deprivation therapy (ADT); * IPSS \<15; * Age: ≥ 18 years old; * Karnofsky performance status ≥70; * Patients able to tolerate long (approximately 60 minutes) treatment time; * Patients who are willing and able to comply with scheduled visits, treatment, and other trial procedures.

Exclusion criteria

* Previous radical treatment for prostate cancer - either radiation therapy (external or brachytherapy), surgery, TUR-P, cryosurgery, or HIFU; * Contraindications for MRI, e.g., patients with metal fragments or implanted devices that are not MR compatible such as certain types of pacemakers and aneurysm clips or severe claustrophobia; * Lack of safe contraception; * Known or suspected non-compliance, drug or alcohol abuse; * Inability to follow the procedures of the trial, e.g. due to language problems of the participant; * Enrolment of the investigator, his/her family members, employees and other dependent persons.

Design outcomes

Primary

MeasureTime frameDescription
Feasibility of online MR-guided SBRT: Number of fractionsAt the treatment end (treatment duration 2 weeks)Number of fractions when a new online plan on the new patient geometry was successfully generated and applied according to the dosimetric protocol requirements

Secondary

MeasureTime frameDescription
Rates of adverse eventsweekly during treatment and up to 3 months after the treatment endAdverse and severe adverse events measured with Common Terminology Criteria for Adverse Events (CTCAE) (version 5.0)
Quantifying intrafraction motion of the prostate (in mm) and organs-at-risk (in mm)During each treatment session (treatment duration of 2 weeks)Changes in the organ motion (in mm) during a treatment session
Quantifying interfraction motion of the prostate (in mm) and organs-at-risk (in mm)Before each treatment session (treatment duration of 2 weeks)Changes in the organ (the prostate and organs-at-risk \[in mm\]) motion between treatment sessions
Quality of the adapted treatment plan vs. the initial treatment planAt the treatment end (treatment duration 2 weeks)Comparison of radiation doses delivered to the targets and organs-at-risk with the adapted treatment plan vs. the initial treatment plan
Duration of an online adaptive procedureBefore each treatment session (treatment duration 2 weeks)Time needed for adapting a treatment plan

Contacts

Primary ContactNocolaus Andratschke, MD
nicolaus.andratschke@usz.ch+41 44 255 31 50

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026