External Beam Radiation Therapy - Target Volume

A Pilot Study to Develop a Technique for External Beam Radiotherapy After Radical Prostatectomy Based on MRI-Delineation of the Clinical Target Volume

Status

Completed

Phases

Phase 2

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT00230438

Enrollment

Registered

2005-09-30

Start date

2005-01-31

Completion date

2013-05-31

Last updated

2014-01-06

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

Conditions

Prostatic Neoplasms

Brief summary

Delivery of conformal radiation therapy following radical prostatectomy is limited by the inability to define the clinical target volume (CTV). This stems from a poor understanding of patterns of local recurrence and limitations of standard imaging techniques.Magnetic Resonance Imaging (MRI) is a promising modality for imaging the prostatic bed following radical prostatectomy. MRI provides more detailed postoperative anatomy to guide CTV delineation, the ability to document local recurrence patterns, and a method to assess intrafraction prostatic bed motion and deformity to define appropriate planning target volume margins. The aim of this pilot study is to develop a technique for external beam radiation therapy (EBRT) following radical prostatectomy based on MRI-delineation of the CTV. Twenty patients will be enrolled in this pilot, development phase.

Interventions

PROCEDUREExternal Beam Radiotherapy

Study design

Allocation

NON_RANDOMIZED

Intervention model

SINGLE_GROUP

Primary purpose

TREATMENT

Masking

NONE

Eligibility

Sex/Gender

MALE

Age

18 Years to No maximum

Healthy volunteers

Inclusion criteria

* Patients following radical prostatectomy for prostate adenocarcinoma with one or more of the following adverse features: pT2 + positive surgical margins ) pT3 ) PSA ≤ 2ng/ml Persistently elevated PSA at 3 months ) * Patients with initially undetectable PSA following prostatectomy for prostate adenocarcinoma with subsequent PSA relapse * Patients being planned for radiation therapy * No evidence of distant metastases * Age ≥ 18 years * ECOG performance status 0 or 1 * Informed consent

Exclusion criteria

* Contraindications to MRI Patients weighing \>136 kgs (weight limit for the scanner tables) Patients with pacemakers, cerebral aneurysm clips, shrapnel injury or implantable electronic devices not compatible with MRI. * Severe claustrophobia * Inflammatory bowel disease or collagen vascular disease * Previous colorectal surgery * Previous pelvic radiotherapy

Design outcomes

Primary

Measure	Time frame
To develop a technique for MRI-delineation of the clinical target volume (CTV) for EBRT following radical prostatectomy	After data acquisition

Secondary

Measure	Time frame
To compare the location of the urethral anastomosis defined on MRI as compared to a fiducial marker placed under TRUS-guidance adjacent to the anastomosis.	After data acquisition
To measure the amount of intrafraction movement and deformity of the prostatic bed and seminal vesicles with current bowel regimen of daily milk of magnesia using cinematic MRI.	After data acquisition
To compare the reproducibility of clinical target volume and rectal wall volume delineation on MRI and CT.	After data acquisition
To measure the amount of interfraction movement and deformity of the bladder, rectum, and surgical clips within the operative bed using daily cone-beam CT imaging.	After data acquisition
To explore the utility of IV contrast for the delineation of gross tumor recurrence and normal blood vessels.	After data acquisition
To determine the optimal radiation technique that encompasses the MRI-defined PTV whilst respecting bowel and bladder dose constraints.	After data acquisition

Countries

Canada

Outcome results

None listed

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