Reduced Planning Target Volume (PTV) Margins for the Treatment of Prostate Cancer Using the Calypso 4D Localization System

U.S. Army Medical Research Acquisition Activity40 enrolled

Overview

This prospective study evaluates the clinical utility of a novel real-time localization system allowing for smaller volumes of normal tissue to be included in radiation field and determines dosimetric parameters and adverse effect profiles of radiation therapy using this technology. Subjects will have beacon transponders implanted into the prostate to more precisely localize the position of the organ during radiation therapy. Hypothesis: 1. Treatment with highly targeted radiation therapy can be delivered in a daily treatment time consistent with routine clinical practice. 2. Highly targeted radiation therapy with reduced PTV margin will result in a significant decrease in rectal and bladder volume treated.

This study will seek to establish the clinical feasibility of a novel real-time localization and tracking system for use of reduced PTV margins during intensity modulated radiation therapy (IMRT), which will allow treatment of smaller volumes of normal tissue during radiation therapy. Such a reduction in the PTV margins and the exposure of healthy tissue during treatment may allow for several future improvements in prostate radiotherapy including: * decreased acute and chronic adverse effects with similar local tumor control * dose escalation to achieve higher cure rates with similar adverse effects to standard dose treatment * hypofractionation to shorten the time of, and lower the expense of, treatment without increased adverse effects.

Study Type

OBSERVATIONAL

Enrollment

Conditions

Prostate Cancer

Eligibility

Sex: MALEMin age: 40 YearsHealthy volunteers:

Medical Language ↔ Plain English

Inclusion Criteria: * Histologically confirmed adenocarcinoma of the prostate * Low Risk: T1a, T1b, T1c, T2a; Gleason Score less than 7, PSA less than or equal to 10 * Intermediate Risk: T2b, T2c; Gleason Score less than or equal to 7, PSA less than or equal to 15 * Ability to comply with study schedule * Age 40 or older * Zubrod PS 0 or 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 HIV infection * History of chronic prostatitis or chronic cystitis * History of bleeding disorder or any active anticoagulation (excluding ASA) * 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 8). * Prior history of androgen deprivation therapy has been deleted and these patients are allowed on study.

Outcomes

Primary Outcomes

Radiation therapy with reduced treatment margins can be adopted as feasible for routine clinical use

During each radiation treatment fraction, therapists will record set up time, treatment time, total time and number of treatment interventions (repositioning/pausing) as well as the duration of the intervention caused by organ/target motion beyond planning target volume (PTV) margin using real time localization and tracking.

Time frame: Approximately 8.5 weeks (43 fractions per pt.)

Secondary Outcomes

Analyze dosimetric characteristics of treatment planning

Standard methods vs. reduced planning target volume expansions will be analyzed: 1. Dose Volume Histogram (DVH), bladder and rectum 2. Volume receiving 77.4Gy by the prescription dose (V77.4Gy), V70Gy, and V50Gy of bladder and rectum

Time frame: usually within the first 2 weeks after beacon placement (done at simulation CT)

Assess incidence of acute bladder and rectal toxicity

toxicity is based on the RTOG/NCI CTC and EPIC quality of life survey.

Time frame: approximately 25 months (assessed prior to beacons are placed and then throughout treatment and follow-up)