Post-prostatectomy Daily Target Guided Radiotherapy Using Real-Time, State-of-the-Art Motion Tracking With the Calypso 4D Localization System: A Feasibility Study
This prospective study evaluates the clinical utility of a novel real-time localization
system of the prostate bed during adjuvant or salvage radiotherapy after radical
prostatectomy. This study will also determine positioning errors using daily cone-beam
computed tomography in patients set up with the Calypso 4D Localization System. Subjects
will have BeaconĀ® Transponders implanted into the prostate bed. The Calypso 4D Localization
System will localize the position of the prostate bed. Cone beam CT will be used daily to
measure inter-transponder distance. The Calypso system will also track the prostate bed
position in real time during the entire radiation treatment. The treatments will be adjusted
as required to ensure accurate treatment of the clinical target volume. The time of, the
number, and extent of adjustments will be recorded for analysis.
Daily cone-beam computed tomography images will also be retrospectively analyzed to assess
for adequate target coverage. The analysis will be performed retrospectively through manual
3-D registration of the cone-beam CT dataset with the treatment planning CT scan. This
information will determine the margins necessary for the PTV using the Calypso 4D
Localization System and potentially may allow a reduction in the PTV volumes on future
studies.
Observational
Observational Model: Cohort, Time Perspective: Prospective
Interfraction prostate bed motion
For each fraction, measurements from the registered CTV (clinical target volume) at the midline will be obtained to structures at 3 points to assess for the degree of motion. Inferior (defined as 8 mm below VUA) Superior (top of seminal vesicle remnant or superior most CTV slice) Middle (defined as the slice equally distant from the inferior and superior slices above)
Approximately 7.5 weeks (36-39 fractions per pt.)
No
Dusten Macdonald, MD
Principal Investigator
Department of the Army
United States: Federal Government
W81XWH-08-2-0174, A-15214.3
NCT01624623
March 2010
September 2014
Name | Location |
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Madigan Healthcare System | Tacoma, Washington 98431 |