External Immobilization Compared to Limited Immobilization Using a Novel Real-time Localization System of the Prostate

This prospective study at MAMC evaluates the utility of a rigid pelvic external immobilization compared to limited immobilization using a novel real-time localization system of the prostate. The sample population will include patients referred to the radiation oncology services of both facilities for definitive treatment of prostate cancer. The study will enroll 20 subjects from MAMC and evaluate data on 860 radiation therapy fractions. Subjects will have Beacon® Transponders implanted into the prostate to more precisely localize the position of the organ during radiation therapy. They will be randomized to rigid pelvic immobilization using a Vac-Lok® system or limited immobilization with a band around the patient's feet. They will then undergo radiation therapy planning with standard planning target margins. The Calypso® 4D Localization System will monitor, in real time, the position of the prostate target and adjust radiation treatments as required to ensure accurate treatment of the prostate gland. The time of, the number, and extent of adjustments will be recorded for analysis. Hypothesis: 1. When treating only the prostate, treatment with rigid pelvic immobilization is not necessary when using real-time, state-of-the-art motion tracking of the prostate.

Sex

Male

Minimum age

40 Years

Inclusion Criteria:

* Histologically confirmed adenocarcinoma of the prostate
* Stage T1 -T3a, N0 or NX, M0
* Ability to comply with study schedule
* Age 40 or older
* Zubrod PS 0 or 1 (appendix 1)
* Signed informed consent

Exclusion Criteria:

* Node positive or metastatic prostate cancer
* Prior treatment of prostate cancer with surgery, chemotherapy, cryotherapy or brachytherapy
* History of prior pelvic radiotherapy
* History of abdominoperineal resection
* History of inflammatory bowel disease or connective tissue disease
* History of HIV infection
* History of chronic prostatitis or chronic cystitis
* History of bleeding disorder or any active anticoagulation (excluding ASA) which cannot be safely discontinued for beacon placement
* PT or INR outside normal range for institution
* Active implanted devices such as cardiac pacemakers and automatic defibrillators.
* Prosthetic implants in the pelvic region that contain metal or conductive materials (eg., an artificial hip).
* Patients with maximum anterior-posterior separation through the torso minus the height of the center of the prostate greater than 17 cm (technical reason for Calypso System, see appendix 5).