SBRT vs. Conventional Fractionation With HDR Boost for Prostate Cancer

Study Overview
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Brief Summary
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Random assignment between SBRT and conventionally fractionated boost following HDR brachytherapy for prostate cancer.

Detailed Description
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Many treatment options exist for prostate cancer. One common treatment approach is to combine high-dose rate (HDR) brachytherapy (temporary insertion of radiation into the prostate) and external beam radiation. External beam radiation typically requires daily radiation treatment for three to five weeks. Improvements to radiation planning and delivery has allowed stereotactic body radiation therapy (SBRT) to be implemented in many types of cancer. SBRT has been implemented as a standard treatment option after HDR brachytherapy in response to the COVID pandemic. We are seeking to evaluate whether it is feasible to randomly assign men between SBRT (which will be five treatments of radiation or conventional radiation (3-5 weeks of daily treatment) following HDR brachytherapy

Official Title
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A Randomized Feasibility Trial of Stereotactic Body Radiotherapy Versus Conventional Fractionation With High Dose-rate (HDR) Brachytherapy Boost for Prostate Cancer

Conditions
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Prostate Cancer

Intervention / Treatment
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* Radiation: Sterotactic Body Radiotherapy
* Radiation: Conventionally Fractionated Radiation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 18 or older Informed consent for treatment and study participation completed Pathologically proven diagnosis of prostate adenocarcinoma ECOG Performance Status 0-2 No prior history of pelvic radiotherapy, brachytherapy, cryosurgery, HIFU, TURP or radical prostatectomy Exclusion Criteria: Presence of nodal or distant metastasis on staging MRI or CT Abdomen/Pelvis and Bone scan within 90 days of enrolment (CT/MRI/Bone Scan are only required if the clinical risk of metastatic disease is sufficient to warrant these scans) Plan for adjuvant chemotherapy post-radiotherapy Serious medical comorbidities or other contraindications to HDR brachytherapy Presence of inflammatory bowel disease Presence of connective tissue disorder seen as a contraindication to radiotherapy Medically unfit for general/spinal anesthesia Unable or unwilling to complete questionnaires

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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Male

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Conventional Fractionated Radiation<br>Prostate Only Radiation - 37.5Gy in 15 daily fractions to the prostate and proximal/entire seminal vesicle Prostate + Nodal Radiation - 46Gy in 23 daily fractions to the prostate, seminal vesicle and regional lymph nodes | Radiation: Conventionally Fractionated Radiation<br>* External beam radiation therapy treatment<br>|
| Experimental: Stereotactic Body Radiotherapy<br>Prostate Only Radiation - 25Gy in 5 fractions to the prostate and proximal/entire seminal vesicle Prostate + Nodal Radiation - 25Gy in 5 fractions to the prostate, seminal vesicle and regional lymph nodes | Radiation: Sterotactic Body Radiotherapy<br>* Hypofractionated stereotactic radiation treatment.<br>* Other names: SBRT;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Treatment Feasibility | The proportion of patients accepting of being randomized divided by the number of patients approached for the study. | 18mo - 2 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| QOL | Urinary, bowel and sexual health-related quality of life measured by the Expanded Prostate Cancer Index Composite (EPIC) domains over the study period. Each domain is normalized from 0 to 100, with a higher score indicating better outcome. | 7 years | 
| Treatment Toxicity | Proportion of patients with urinary, bowel and sexual Grade 2 and 3 toxicity measured by CTCAE v5.0 throughout the study period. | 7 years | 
| Cumulative biochemical failure | Defined as the time of enrolment to biochemical failure (based on the Phoenix definition, PSA nadir plus 2) | 7 years | 
| Overall Survival | Defined as time of enrollment to death from any cause | 7 years | 
| Cancer Free Survival | Defined as time of enrolment to death attributed to prostate cancer | 7 years | 
| Metastasis Free Survival | Defined as time of enrolment to development of metastasis or death from any cause | 7 years | 
| Freedom From Local Failure | Defined as time of enrolment to first local recurrence | 7 years | 
| Freedom From Regional Failure | Defined as time of enrolment to first regional recurrence | 7 years | 
| ADT Free Survival | Defined as time of enrolment to salvage ADT use or death from any cause | 7 Years | 
| PSA nadir | PSA nadir at 4-years post treatment | 6 years |