Stereotactic Ablative Radiotherapy (SABR) for Low Risk Prostate Cancer With Injectable Rectal Spacer
|ClinicalTrials.gov Identifier: NCT02353832|
Recruitment Status : Active, not recruiting
First Posted : February 3, 2015
Results First Posted : May 7, 2019
Last Update Posted : March 23, 2020
|Condition or disease||Intervention/treatment||Phase|
|Prostate Cancer||Device: Injectable Rectal Spacer (SpaceOAR, Duraseal or equivalent)||Phase 2|
A phase II study to assess safety and efficacy of the spacer injection process, ability of the spacer to effectively provide the space necessary to reduce acute events in the rectum, and also meet the SABR based rectal constraints, and to monitor stability of this process during SABR. Unlike IMRT, which uses smaller dose/fraction, when using such high dose/fraction, even a few mm of shift in spacer positioning may impact the dose that the rectum receives, and therefore, a rigorous study of stability of material during the SABR treatments will need to be determined. If there is some shift, by doing this study, we may be able to determine the margin of error that will be necessary in considering rectal organ dosimetry, based on the possible shift in positiong that may occur with the spacer over time.
As the SABR therapy is strictly local, we will select for patients with prostate cancer locally confined to the prostate gland. As such, we will select eligibility criteria of low risk patients to minimize risk of extraprostatic spread, seminal vesicle invasion, and nodal spread. Hormonal therapy may also be used to shrink prostates that are massively enlarged as this may also help further reduce length of rectum that will be irradiated. As the primary toxicity will likely be mucosal damage, we will avoid enrolling patients with pre-existing mucosal dysfunction (including those with previous radiation, TURP, very large prostate glands, inflammatory bowel disease) and immunosuppressed individuals based on our phase I experience. In this way, patients will be uniformly selected in a fashion that would identify patients likely to receive benefit from the therapy.
|Study Type :||Interventional (Clinical Trial)|
|Actual Enrollment :||44 participants|
|Intervention Model:||Single Group Assignment|
|Masking:||None (Open Label)|
|Official Title:||Phase II Study of Stereotactic Ablative Radiotherapy (SABR) for Low Risk Prostate Cancer With Injectable Rectal Spacer|
|Actual Study Start Date :||November 6, 2014|
|Actual Primary Completion Date :||June 5, 2016|
|Estimated Study Completion Date :||December 18, 2022|
Device: Injectable Rectal Spacer (SpaceOAR, Duraseal or equivalent)
Injectable Rectal Spacer (SpaceOAR, Duraseal or equivalent PEG based product
- Percentage of Participants With Reduction in Acute Per-prostatic Rectal Ulcer Events Events From 90%+ to <70% (Particularly in the Anterior Rectum) [ Time Frame: Median 9 months within the end of radiation treatment ]The effectiveness of rectal spacer use was measured to determine if they are effective at improving protection of rectum from high dose radiation, using rate of rectal ulceration as a surrogate measure of acute effects
- Effectiveness of Space Creation of >= 7.5 mm in Protecting Rectum From Toxicity [ Time Frame: Median 9 months within the end of radiation treatment ]The effectiveness of rectal spacer use was measured to determine if they are effective at improving protection of rectum from high dose radiation, using rate of rectal ulceration as a surrogate measure of acute effects
- Spacer Related Acute Toxicity [ Time Frame: 5 years ]Assess for spacer related acute toxicity. Spacer related toxicity could be related to the procedure itself (bleeding, infection, pain), or secondary effects of spacer (erectile dysfunction, persistent pain and discomfort).
- Spacer Stability by Dimensions [ Time Frame: 1 month ]Determine spacer's stability during course of therapy and to ensure that it is stable enough to reliably use for high dose SABR treatments (using cone beam CTs done during each treatments to measure spacer dimensions).
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT02353832
|United States, New York|
|Memorial Sloan Kettering Cancer Center|
|New York, New York, United States, 10065|
|United States, Texas|
|UT Southwestern Medical Center|
|Dallas, Texas, United States, 75390|
|Principal Investigator:||Michael Folkert, MD||UT Southwestern Medical Center|
|Principal Investigator:||Micheal Zelefsky, MD||Memorial Sloan Kettering Cancer Centre|