Stereotactic Ablative Radiotherapy (SABR) for Low Risk Prostate Cancer With Injectable Rectal Spacer

Phase II Study of Stereotactic Ablative Radiotherapy (SABR) for Low Risk Prostate Cancer With Injectable Rectal Spacer

Status

Completed

Phases

Phase 2

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT02353832

Enrollment

Registered

2015-02-03

Start date

2014-11-06

Completion date

2021-01-05

Last updated

2022-03-25

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Prostate Cancer

Brief summary

The purpose is to determine if use of rectal spacers are effective at improving protection of rectum from high dose radiation, using rate of rectal ulceration as a surrogate measure of acute effects. It is also to determine whether it provides sufficient dosimetric benefits to warrant further clinical investigation in future SABR (Stereotactic Ablative Body Radiation) related clinical studies.

Detailed description

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\[13\]. In this way, patients will be uniformly selected in a fashion that would identify patients likely to receive benefit from the therapy.

Interventions

DEVICEInjectable Rectal Spacer (SpaceOAR, Duraseal or equivalent)

Injectable Rectal Spacer (SpaceOAR, Duraseal or equivalent PEG based product

Study design

Allocation

Intervention model

SINGLE_GROUP

Primary purpose

TREATMENT

Masking

NONE

Eligibility

Sex/Gender

MALE

Age

18 Years to 99 Years

Healthy volunteers

Inclusion criteria

* All patients must be willing and capable to provide informed consent to participate in the protocol. * Eligible patients must have appropriate staging studies identifying them as AJCC stage T1 (a, b, or c) or T2a or T2b adenocarcinoma of the prostate gland. The patient should not have direct evidence of regional or distant metastases after appropriate staging studies. Histologic confirmation of cancer will be required by biopsy performed within 180 days of registration. * The patient's Zubrod performance status must be 0-2. * The Gleason score should be less than or equal to 6 or 3+4 if \< 50% of a 12 core biopsy was involved. * The serum PSA should be less than or equal to 10 ng/ml. * Study entry PSA must not be obtained during the following time frames: 10 day period following prostate biopsy; following initiation of ADT; within 30 days after discontinuation of finasteride; or within 90 days after discontinuation of dutasteride. * Age ≥ 18 years. * Patients may have used prior hormonal therapy, but it should be limited to no more than 9 months of therapy prior to enrollment. * The ultrasound, or CT based volume estimation of the patient's prostate gland should be ≤ 60 grams.

Exclusion criteria

* Subjects who have had previous pelvic radiotherapy or have had chemotherapy or surgery for prostate cancer. * Subjects who have plans to receive other concomitant or post treatment adjuvant antineoplastic therapy while on this protocol including surgery, cryotherapy, conventionally fractionated radiotherapy, hormonal therapy, or chemotherapy given as part of the treatment of prostate cancer. * Subjects who have undergone previous transurethral resection of the prostate (TURP) or cryotherapy to the prostate. Subjects who have significant urinary obstructive symptoms; AUA score must be ≤15 (alpha blockers allowed). * Subjects who have a history of significant psychiatric illness. * Men of reproductive potential who do not agree that they or their partner will use an effective contraceptive method such as condom/diaphragm and spermacidal foam, intrauterine device (IUD), or prescription birth control pills. * Prior invasive malignancy (except non-melanomatous skin cancer) unless disease free for a minimum of 3 years (e.g., carcinoma in situ of the breast, oral cavity, or cervix are all permissible). * Severe, active co-morbidity, defined as follows: * Unstable angina and/or congestive heart failure requiring hospitalization within the last 6 months. * Transmural myocardial infarction within the last 6 months. * Acute bacterial or fungal infection requiring intravenous antibiotics at the time of registration. * Chronic Obstructive Pulmonary Disease exacerbation or other respiratory illness requiring hospitalization or precluding study therapy within 30 days before registration. * Hepatic insufficiency resulting in clinical jaundice and/or coagulation defects; note, however, that laboratory tests for liver function and coagulation parameters are not required for entry into this protocol. * Acquired Immune Deficiency Syndrome (AIDS) based upon current CDC definition; note, however, that HIV testing is not required for entry into this protocol. The need to exclude patients with AIDS from this protocol is necessary because the treatments involved in this protocol may be significantly immunosuppressive. Protocol-specific requirements may also exclude immuno-compromised patients. * Patients with history of inflammatory colitis (including Crohn's Disease and Ulcerative colitis) are not eligible. * Subjects with a known allergy to polyethylene glycol hydrogel (spacer material) or contraindication to spacer products (Duraseal or SpaceOAR). * Subjects with evidence of extraprostatic extension (T3a) or seminal vesicle involvement (T3b) on clinical evaluation.

Design outcomes

Primary

Measure	Time frame	Description
Percentage of Participants With Reduction in Acute Per-prostatic Rectal Ulcer Events Events From 90%+ to <70% (Particularly in the Anterior Rectum)	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	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

Secondary

Measure	Time frame	Description
Determine Spacer's Ability to Change Percent Rectal Circumference (PRC) Receiving 24 Gy.	1 month	Determine spacer's ability to change percent rectal circumference (PRC) receiving 24 and 39 Gy by at least 50%. This will be determined by using CT planning studies for dosimetric analysis before and after spacer placement.
Acute (Within 270 Days of Treatment) SABR-related Gastrointestinal (GI) Toxicities	270 days	Acute gastrointestinal (GI) toxicity is defined as grade 1-5 toxicity occurring prior to 270 days from the start of protocol treatment. It is graded based on CTCAE v4.0.
Acute (Within 270 Days of Treatment) SABR-related Genitourinary (GU) Toxicities	270 days	Acute genitourinary (GU)toxicity is defined as grade 1-5 toxicity occurring prior to 270 days from the start of protocol treatment. It is graded based on CTCAE v4.0.
Chronic (>270 Days From Treatment) SABR-related Genitourinary (GU) Toxicities	From day 271 up to 540 days	Delayed genitourinary (GU) toxicity is defined as grade 1-5 toxicity occurring after 270 days from the start of protocol treatment. It is graded based on CTCAE v4.0. Adverse events will be graded by a numerical score according to the defined NCI Common Terminology Criteria for Adverse Events (NCI CTCAE V4.0) and version number 4.0 specified in the protocol. Grade 1: Mild; Grade 2: Moderate; Grade 3: Severe or medically significant but not immediately life threatening; Grade 4: Life threatening consequences; Grade 5: Death related to the adverse event.
Chronic (>270 Days From Treatment) SABR-related Gastrointestinal (GI) Toxicities	From day 271 up to 540 days	Delayed gastrointestinal (GI) toxicity is defined as grade 1-5 toxicity occurring after 270 days from the start of protocol treatment. It is graded based on CTCAE v4.0. Adverse events will be graded by a numerical score according to the defined NCI Common Terminology Criteria for Adverse Events (NCI CTCAE V4.0) and version number 4.0 specified in the protocol. Grade 1: Mild; Grade 2: Moderate; Grade 3: Severe or medically significant but not immediately life threatening; Grade 4: Life threatening consequences; Grade 5: Death related to the adverse event.
Acute Non-GI (Gastrointestinal) and Non-GU (Genitourinary) Toxicity- Irritative	270 days	Toxicity will be assessed according to the NCI Common Toxicity Criteria for Adverse Events (CTCAE), version 4.0.
Acute Non-GI (Gastrointestinal) and Non-GU (Genitourinary) Toxicity-Obstructive	270 days	Toxicity will be assessed according to the NCI Common Toxicity Criteria for Adverse Events (CTCAE), version 4.0.
Acute Non-GI (Gastrointestinal) and Non-GU (Genitourinary) Toxicity-Reproductive.	270 days	Toxicity will be assessed according to the NCI Common Toxicity Criteria for Adverse Events (CTCAE), version 4.0.
Chronic Non-GI (Gastrointestinal) and Non-GU (Genitourinary) Toxicity-Obstructive.	From day 271 up to 540 days	Toxicity will be assessed according to the NCI Common Toxicity Criteria for Adverse Events (CTCAE), version 4.0. Adverse events will be graded by a numerical score according to the defined NCI Common Terminology Criteria for Adverse Events (NCI CTCAE V4.0) and version number 4.0 specified in the protocol. Grade 1: Mild; Grade 2: Moderate; Grade 3: Severe or medically significant but not immediately life threatening; Grade 4: Life threatening consequences; Grade 5: Death related to the adverse event.
Chronic Non-GI (Gastrointestinal) and Non-GU (Genitourinary) Toxicity-Reproductive.	From day 271 up to 540 days	Toxicity will be assessed according to the NCI Common Toxicity Criteria for Adverse Events (CTCAE), version 4.0. Adverse events will be graded by a numerical score according to the defined NCI Common Terminology Criteria for Adverse Events (NCI CTCAE V4.0) and version number 4.0 specified in the protocol. Grade 1: Mild; Grade 2: Moderate; Grade 3: Severe or medically significant but not immediately life threatening; Grade 4: Life threatening consequences; Grade 5: Death related to the adverse event.
Chronic Non-GI (Gastrointestinal) and Non-GU (Genitourinary) Toxicity-Irritative.	From day 271 up to 540 days	Toxicity will be assessed according to the NCI Common Toxicity Criteria for Adverse Events (CTCAE), version 4.0. Adverse events will be graded by a numerical score according to the defined NCI Common Terminology Criteria for Adverse Events (NCI CTCAE V4.0) and version number 4.0 specified in the protocol. Grade 1: Mild; Grade 2: Moderate; Grade 3: Severe or medically significant but not immediately life threatening; Grade 4: Life threatening consequences; Grade 5: Death related to the adverse event.
Freedom From Biochemical Recurrence	4 year	Biochemical failure RTOG-ASTRO definition (also known as Phoenix definition) - Thus, when the PSA rises by more than 2 ng/ml above the lowest level (nadir) achieved after treatment, biochemical failure has occurred and the date of the failure is recorded at the time the nadir plus 2 ng/ml level is reached
Overall Survival	5 year	Overall survival as measured by percentage of participants who survived at 5 years. The survival time will be measured from the date of accession to the date of death.
Disease-specific Survival	5 year	Percentage of patients who did not die from prostate cancer at 5 years.
Percentage of Participants With Spacer Related Acute Toxicity	270 days	Assess 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). Adverse events will be graded by a numerical score according to the defined NCI Common Terminology Criteria for Adverse Events (NCI CTCAE V4.0) and version number 4.0 specified in the protocol. Grade 1: Mild; Grade 2: Moderate; Grade 3: Severe or medically significant but not immediately life threatening; Grade 4: Life threatening consequences; Grade 5: Death related to the adverse event.
Regional Relapse	3 years	Percentage of patients without regional relapse at 3 years. Regional relapse will be measured from the date of study entry to the date of documented regional nodal recurrence or distant disease relapse.
Distant Relapse	3 years	Percentage of patients without distant relapse at 3 years. Distant relapse will be measured from the date of study entry to the date of documented regional nodal recurrence or distant disease relapse.
EPIC (Expanded Prostate Cancer Index Composite) Bowel Function	18 months	Outcomes for bowel function and effect on quality of life. Expanded Prostate Cancer Index Composite (EPIC) bowel function score (range, 0 (worst) -100 (best)). EPIC bowel urgency (percentages are for men reporting more than a small problem). EPIC bowel frequency (percentages are for men reporting more than a small problem). EPIC bowel leakage or fecal incontinence (percentages are for men having fecal incontinence at least once per week). EPIC bloody stools (percentages are for men having bloody stools half the time or more). EPIC bowel, pelvic, or rectal pain (percentages are for men reporting more than a small problem). EPIC bowel habits (percentages are for men reporting more than a small problem).
EPIC (Expanded Prostate Cancer Index Composite) Bowel Frequency	18 months	Outcomes for bowel function and effect on quality of life. Expanded Prostate Cancer Index Composite (EPIC) bowel function score (range, 0-100). EPIC bowel urgency (percentages are for men reporting more than a small problem). EPIC bowel frequency (percentages are for men reporting more than a small problem). EPIC bowel leakage or fecal incontinence (percentages are for men having fecal incontinence at least once per week). EPIC bloody stools (percentages are for men having bloody stools half the time or more). EPIC bowel, pelvic, or rectal pain (percentages are for men reporting more than a small problem). EPIC bowel habits (percentages are for men reporting more than a small problem).
EPIC (Expanded Prostate Cancer Index Composite) Bloody Stools	18 months	Outcomes for bowel function and effect on quality of life. Expanded Prostate Cancer Index Composite (EPIC) bowel function score (range, 0-100). EPIC bowel urgency (percentages are for men reporting more than a small problem). EPIC bowel frequency (percentages are for men reporting more than a small problem). EPIC bowel leakage or fecal incontinence (percentages are for men having fecal incontinence at least once per week). EPIC bloody stools (percentages are for men having bloody stools half the time or more). EPIC bowel, pelvic, or rectal pain (percentages are for men reporting more than a small problem). EPIC bowel habits (percentages are for men reporting more than a small problem).
EPIC (Expanded Prostate Cancer Index Composite) Bowel Habits	18 months	Outcomes for bowel function and effect on quality of life. Expanded Prostate Cancer Index Composite (EPIC) bowel function score (range, 0-100). EPIC bowel urgency (percentages are for men reporting more than a small problem). EPIC bowel frequency (percentages are for men reporting more than a small problem). EPIC bowel leakage or fecal incontinence (percentages are for men having fecal incontinence at least once per week). EPIC bloody stools (percentages are for men having bloody stools half the time or more). EPIC bowel, pelvic, or rectal pain (percentages are for men reporting more than a small problem). EPIC bowel habits (percentages are for men reporting more than a small problem).
EPIC (Expanded Prostate Cancer Index Composite) Bowel Urgency	18 months	Outcomes for bowel function and effect on quality of life. Expanded Prostate Cancer Index Composite (EPIC) bowel function score (range, 0-100). EPIC bowel urgency (percentages are for men reporting more than a small problem). EPIC bowel frequency (percentages are for men reporting more than a small problem). EPIC bowel leakage or fecal incontinence (percentages are for men having fecal incontinence at least once per week). EPIC bloody stools (percentages are for men having bloody stools half the time or more). EPIC bowel, pelvic, or rectal pain (percentages are for men reporting more than a small problem). EPIC bowel habits (percentages are for men reporting more than a small problem).
EPIC (Expanded Prostate Cancer Index Composite) Bowel Leakage/Fecal Incontinence	18 months	Outcomes for bowel function and effect on quality of life. Expanded Prostate Cancer Index Composite (EPIC) bowel function score (range, 0-100). EPIC bowel urgency (percentages are for men reporting more than a small problem). EPIC bowel frequency (percentages are for men reporting more than a small problem). EPIC bowel leakage or fecal incontinence (percentages are for men having fecal incontinence at least once per week). EPIC bloody stools (percentages are for men having bloody stools half the time or more). EPIC bowel, pelvic, or rectal pain (percentages are for men reporting more than a small problem). EPIC bowel habits (percentages are for men reporting more than a small problem).
EPIC (Expanded Prostate Cancer Index Composite) Bowel Pelvic/Rectal Pain	18 months	Outcomes for bowel function and effect on quality of life. Expanded Prostate Cancer Index Composite (EPIC) bowel function score (range, 0-100). EPIC bowel urgency (percentages are for men reporting more than a small problem). EPIC bowel frequency (percentages are for men reporting more than a small problem). EPIC bowel leakage or fecal incontinence (percentages are for men having fecal incontinence at least once per week). EPIC bloody stools (percentages are for men having bloody stools half the time or more). EPIC bowel, pelvic, or rectal pain (percentages are for men reporting more than a small problem). EPIC bowel habits (percentages are for men reporting more than a small problem).
EPIC (Expanded Prostate Cancer Index Composite) Urinary Function	18 months	Outcomes for urinary function and effect on quality of life. Expanded Prostate Cancer Index Composite (EPIC) urinary function score (range, 0 (worst)-100 (best)). EPIC urinary irritation or obstruction (range, 0-100).EPIC urinary incontinence (range, 0-100).
EPIC (Expanded Prostate Cancer Index Composite) Urinary Irritative/Obstructive	18 months	Outcomes for urinary function and effect on quality of life. Expanded Prostate Cancer Index Composite (EPIC) urinary function score (range, 0-100). EPIC urinary irritation or obstruction (range, 0 (worst)-100 (best)).EPIC urinary incontinence (range, 0-100).
EPIC (Expanded Prostate Cancer Index Composite) Urinary Incontinence	18 months	Outcomes for urinary function and effect on quality of life. Expanded Prostate Cancer Index Composite (EPIC) urinary function score (range, 0-100). EPIC urinary irritation or obstruction (range, 0-100).EPIC urinary incontinence (range, 0 (worst)-100 (best)).
AUA (American Urological Association) Quality of Life Questionnaire	18 months	AUA Questionnaire is used to measure urinary symptoms. AUA uses a 7-item self-report measure used to assess urinary urgency, frequency, and voiding symptoms. SYMPTOM SCORE: 0-7 (Mild) 8-19 (Moderate) 20-35 (Severe)
Local Relapse	3 year	Percentage of patients without local relapse at 3 years. Local relapse will be measured from the date of study entry to the date of documented local relapse as determined by clinical exam.
Determine Spacer's Ability to Change Percent Rectal Circumference (PRC) Receiving 39 Gy	1 month	Determine spacer's ability to change percent rectal circumference (PRC) receiving 39 Gy by at least 50%. This will be determined by using CT planning studies for dosimetric analysis before and after spacer placement.

Countries

United States

Participant flow

Participants by arm

Arm	Count
Single Arm: Injectable Rectal Spacer Injectable Rectal Spacer (SpaceOAR, Duraseal or equivalent): Injectable Rectal Spacer (SpaceOAR, Duraseal or equivalent PEG based product	44
Total	44

Withdrawals & dropouts

Period	Reason	FG000
Overall Study	Ineligible after enrollment	1
Overall Study	Lost to Follow-up	1

Baseline characteristics

Characteristic	Single Arm: Injectable Rectal Spacer
Age, Categorical <=18 years	0 Participants
Age, Categorical >=65 years	17 Participants
Age, Categorical Between 18 and 65 years	27 Participants
Age, Continuous	70 YEARS
Ethnicity (NIH/OMB) Hispanic or Latino	0 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	41 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	3 Participants
Race (NIH/OMB) American Indian or Alaska Native	0 Participants
Race (NIH/OMB) Asian	0 Participants
Race (NIH/OMB) Black or African American	8 Participants
Race (NIH/OMB) More than one race	0 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	1 Participants
Race (NIH/OMB) Unknown or Not Reported	2 Participants
Race (NIH/OMB) White	33 Participants
Region of Enrollment United States	44 participants
Sex: Female, Male Female	0 Participants
Sex: Female, Male Male	44 Participants

Adverse events

Event type	EG000 affected / at risk
deaths Total, all-cause mortality	2 / 44
other Total, other adverse events	20 / 44
serious Total, serious adverse events	0 / 44

Outcome results

Primary

Effectiveness of Space Creation of >= 7.5 mm in Protecting Rectum From Toxicity

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

Time frame: Median 9 months within the end of radiation treatment

Arm	Measure	Value (MEDIAN)
Single Arm: Injectable Rectal Spacer	Effectiveness of Space Creation of >= 7.5 mm in Protecting Rectum From Toxicity	11.5 mm

Primary

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

Population: Observed ulceration rate

Arm	Measure	Value (NUMBER)
Single Arm: Injectable Rectal Spacer	Percentage of Participants With Reduction in Acute Per-prostatic Rectal Ulcer Events Events From 90%+ to <70% (Particularly in the Anterior Rectum)	13.6 percentage of participants

Secondary

Acute Non-GI (Gastrointestinal) and Non-GU (Genitourinary) Toxicity- Irritative

Toxicity will be assessed according to the NCI Common Toxicity Criteria for Adverse Events (CTCAE), version 4.0.

Time frame: 270 days

Arm	Measure	Group	Value (NUMBER)
Single Arm: Injectable Rectal Spacer	Acute Non-GI (Gastrointestinal) and Non-GU (Genitourinary) Toxicity- Irritative	Grade I	44.2 percentage of participants
Single Arm: Injectable Rectal Spacer	Acute Non-GI (Gastrointestinal) and Non-GU (Genitourinary) Toxicity- Irritative	Grade II	37.2 percentage of participants
Single Arm: Injectable Rectal Spacer	Acute Non-GI (Gastrointestinal) and Non-GU (Genitourinary) Toxicity- Irritative	Grade III	2.3 percentage of participants
Single Arm: Injectable Rectal Spacer	Acute Non-GI (Gastrointestinal) and Non-GU (Genitourinary) Toxicity- Irritative	Grade IV	0 percentage of participants
Single Arm: Injectable Rectal Spacer	Acute Non-GI (Gastrointestinal) and Non-GU (Genitourinary) Toxicity- Irritative	Grade V	0 percentage of participants

Secondary

Acute Non-GI (Gastrointestinal) and Non-GU (Genitourinary) Toxicity-Obstructive

Toxicity will be assessed according to the NCI Common Toxicity Criteria for Adverse Events (CTCAE), version 4.0.

Time frame: 270 days

Arm	Measure	Group	Value (NUMBER)
Single Arm: Injectable Rectal Spacer	Acute Non-GI (Gastrointestinal) and Non-GU (Genitourinary) Toxicity-Obstructive	Grade I	41.9 percentage of participants
Single Arm: Injectable Rectal Spacer	Acute Non-GI (Gastrointestinal) and Non-GU (Genitourinary) Toxicity-Obstructive	Grade II	11.6 percentage of participants
Single Arm: Injectable Rectal Spacer	Acute Non-GI (Gastrointestinal) and Non-GU (Genitourinary) Toxicity-Obstructive	Grade III	0 percentage of participants
Single Arm: Injectable Rectal Spacer	Acute Non-GI (Gastrointestinal) and Non-GU (Genitourinary) Toxicity-Obstructive	Grade IV	0 percentage of participants
Single Arm: Injectable Rectal Spacer	Acute Non-GI (Gastrointestinal) and Non-GU (Genitourinary) Toxicity-Obstructive	Grade V	0 percentage of participants

Secondary

Acute Non-GI (Gastrointestinal) and Non-GU (Genitourinary) Toxicity-Reproductive.

Toxicity will be assessed according to the NCI Common Toxicity Criteria for Adverse Events (CTCAE), version 4.0.

Time frame: 270 days

Arm	Measure	Group	Value (NUMBER)
Single Arm: Injectable Rectal Spacer	Acute Non-GI (Gastrointestinal) and Non-GU (Genitourinary) Toxicity-Reproductive.	Grade I	32.6 percentage of participants
Single Arm: Injectable Rectal Spacer	Acute Non-GI (Gastrointestinal) and Non-GU (Genitourinary) Toxicity-Reproductive.	Grade II	14.0 percentage of participants
Single Arm: Injectable Rectal Spacer	Acute Non-GI (Gastrointestinal) and Non-GU (Genitourinary) Toxicity-Reproductive.	Grade III	0 percentage of participants
Single Arm: Injectable Rectal Spacer	Acute Non-GI (Gastrointestinal) and Non-GU (Genitourinary) Toxicity-Reproductive.	Grade IV	0 percentage of participants
Single Arm: Injectable Rectal Spacer	Acute Non-GI (Gastrointestinal) and Non-GU (Genitourinary) Toxicity-Reproductive.	Grade V	0 percentage of participants

Secondary

Acute (Within 270 Days of Treatment) SABR-related Gastrointestinal (GI) Toxicities

Acute gastrointestinal (GI) toxicity is defined as grade 1-5 toxicity occurring prior to 270 days from the start of protocol treatment. It is graded based on CTCAE v4.0.

Time frame: 270 days

Arm	Measure	Group	Value (NUMBER)
Single Arm: Injectable Rectal Spacer	Acute (Within 270 Days of Treatment) SABR-related Gastrointestinal (GI) Toxicities	Grade I	58.1 percentage of participants
Single Arm: Injectable Rectal Spacer	Acute (Within 270 Days of Treatment) SABR-related Gastrointestinal (GI) Toxicities	Grade II	23.3 percentage of participants
Single Arm: Injectable Rectal Spacer	Acute (Within 270 Days of Treatment) SABR-related Gastrointestinal (GI) Toxicities	Grade III	0 percentage of participants
Single Arm: Injectable Rectal Spacer	Acute (Within 270 Days of Treatment) SABR-related Gastrointestinal (GI) Toxicities	Grade IV	0 percentage of participants
Single Arm: Injectable Rectal Spacer	Acute (Within 270 Days of Treatment) SABR-related Gastrointestinal (GI) Toxicities	Grade V	0 percentage of participants

Secondary

Acute (Within 270 Days of Treatment) SABR-related Genitourinary (GU) Toxicities

Acute genitourinary (GU)toxicity is defined as grade 1-5 toxicity occurring prior to 270 days from the start of protocol treatment. It is graded based on CTCAE v4.0.

Time frame: 270 days

Arm	Measure	Group	Value (NUMBER)
Single Arm: Injectable Rectal Spacer	Acute (Within 270 Days of Treatment) SABR-related Genitourinary (GU) Toxicities	Grade I	65.1 percentage of participants
Single Arm: Injectable Rectal Spacer	Acute (Within 270 Days of Treatment) SABR-related Genitourinary (GU) Toxicities	Grade II	46.5 percentage of participants
Single Arm: Injectable Rectal Spacer	Acute (Within 270 Days of Treatment) SABR-related Genitourinary (GU) Toxicities	Grade III	2.3 percentage of participants
Single Arm: Injectable Rectal Spacer	Acute (Within 270 Days of Treatment) SABR-related Genitourinary (GU) Toxicities	Grade IV	0 percentage of participants
Single Arm: Injectable Rectal Spacer	Acute (Within 270 Days of Treatment) SABR-related Genitourinary (GU) Toxicities	Grade V	0 percentage of participants

Secondary

AUA (American Urological Association) Quality of Life Questionnaire

AUA Questionnaire is used to measure urinary symptoms. AUA uses a 7-item self-report measure used to assess urinary urgency, frequency, and voiding symptoms. SYMPTOM SCORE: 0-7 (Mild) 8-19 (Moderate) 20-35 (Severe)

Time frame: 18 months

Arm	Measure	Value (MEDIAN)
Single Arm: Injectable Rectal Spacer	AUA (American Urological Association) Quality of Life Questionnaire	8 score on a scale

Secondary

Chronic (>270 Days From Treatment) SABR-related Gastrointestinal (GI) Toxicities

Delayed gastrointestinal (GI) toxicity is defined as grade 1-5 toxicity occurring after 270 days from the start of protocol treatment. It is graded based on CTCAE v4.0. Adverse events will be graded by a numerical score according to the defined NCI Common Terminology Criteria for Adverse Events (NCI CTCAE V4.0) and version number 4.0 specified in the protocol. Grade 1: Mild; Grade 2: Moderate; Grade 3: Severe or medically significant but not immediately life threatening; Grade 4: Life threatening consequences; Grade 5: Death related to the adverse event.