This study will evaluate the daily use of a unique daily organ tracking system on target localization in patients treated with radiation therapy after radical prostatectomy for prostate cancer. Improved coverage of the target volume with radiotherapy could result in improved cancer control rates and decreased coverage of surrounding structures potentially decreasing treatment toxicity.
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 Beacon® 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.
Study Type
OBSERVATIONAL
Enrollment
20
Madigan Healthcare System
Tacoma, Washington, United States
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. 1. Inferior (defined as 8 mm below VUA) 2. Superior (top of seminal vesicle remnant or superior most CTV slice) 3. Middle (defined as the slice equally distant from the inferior and superior slices above)
Time frame: Approximately 7.5 weeks (36-39 fractions per pt.)
Intrafraction prostate bed motion
Calypso session reports measuring intrafraction motion in x,y,z axis will be recorded and analyzed.
Time frame: Approximately 7.5 weeks (36-39 fractions per pt.)
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.