An interventional study of Biopsy Procedure and Computed Tomography in Stage I Prostate Cancer AJCC v8, Stage II Prostate Cancer AJCC v8 and Stage IIIA Prostate Cancer AJCC v8, sponsored by City of Hope Medical Center. Not yet recruiting at 1 site in United States. Open to male participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-08-17.
Sponsored by City of Hope Medical Center · Not applicable, Interventional, and Treatment
This clinical trial studies the side effects and how well magnetic resonance (MR)-guided stereotactic body radiation therapy (SBRT) works in treating patients with prostate cancer. SBRT is a type of external radiation therapy that uses special equipment to position a patient and precisely deliver radiation to tumors in the body (except the brain). The total dose of radiation is divided into smaller doses given over several days. This type of radiation therapy helps spare normal tissue. MR-guided SBRT uses magnetic resonance imaging (MRI) to define and localize the area to be treated, which may help provide more accurate delivery of SBRT and lower side effects. MR-guided SBRT may be safe, tolerable, and/or effective in treating patients with prostate cancer.
PRIMARY OBJECTIVE:
I. To determine the safety of performing focal MR-guided SBRT.
SECONDARY OBJECTIVES:
I. To assess the tolerability of focal MR-guided SBRT. II. To characterize changes in urinary, bowel and sexual function in patients receiving focal MR-guided SBRT.
III. To characterize changes in prostate symptoms in patients receiving focal MR-guided SBRT.
IV. To characterize changes in sexual health in patients receiving focal MR-guided SBRT.
V. To estimate the rate of biochemical recurrence after receiving focal MR-guided SBRT.
VI. To estimate the rate of in-field prostate recurrence after receiving focal MR-guided SBRT.
VII. To estimate the rate of out-of-field prostate recurrence after receiving focal MR-guided SBRT.
VIII. To estimate the rate of salvage therapy after receiving focal MR-guided SBRT.
IX. To estimate the time to local radiographic progression after receiving focal MR-guided SBRT.
X. To estimate the time to distant radiographic progression after receiving focal MR-guided SBRT.
EXPLORATORY OBJECTIVES:
I. To characterize changes in imaging features from pre-treatment to post-treatment, assessed using multiparametric prostate MRI (including T2 weighted imaging, apparent diffusion coefficient (ADC) values, and dynamic contrast-enhanced (DCE) perfusion metrics, as well as radiomic features, and prostate-specific membrane antigen positron emission tomography (PSMA PET) imaging, if available.
II. To characterize the intraprostatic tumor microenvironment and clonal dynamics following focal SBRT using surveillance biopsy tissue obtained at 2 years post-treatment, with comparison of cores sampled within versus outside the radiation field.
OUTLINE:
Patients undergo five treatment fractions of MR-guided SBRT over 30-45 minutes each up to three times a week (TIW) over approximately 2 weeks in the absence of disease progression or unacceptable toxicity. Patients also undergo MRI and biopsy throughout the study as well as computed tomography (CT) on study.
After completion of study treatment, patients are followed up at 90 days, 12 months, and then every 6 months for 4 years.
Documented informed consent of the participant and/or Legally Authorized Representative
National Comprehensive Cancer Network (NCCN) low-risk or intermediate-risk prostate cancer, defined as:
Intermediate-risk (one or more of the following intermediate risk factors [IRFs]): PSA 10-20 ng/mL, grade group 2 or 3 (Gleason 3+4 or 4+3), or clinical stage T2b-T2c
Unfavorable intermediate-risk (one or more of the following): 2 or 3 IRFs, grade group 3, ≥ 50% cores positive
Agreement by males of childbearing potential to use an effective method of birth control or abstain from heterosexual activity for the course of the study through at least 4 months after the last dose of protocol therapy
Exclusion Criteria:
Contraindication to magnetic resonance imaging, including but not limited to:
Patients undergo five treatment fractions of MR-guided SBRT over 30-45 minutes each up to TIW over approximately 2 weeks in the absence of disease progression or unacceptable toxicity. Patients also undergo MRI and biopsy throughout the study as well as CT on study.
Procedure: Biopsy Procedure · Procedure: Computed Tomography · Other: Electronic Health Record Review · Procedure: Magnetic Resonance Imaging · Radiation: MRI-guided Stereotactic Body Radiation Therapy · Other: Questionnaire Administration
Undergo biopsy
Also known as: Biopsy, BIOPSY_TYPE, Bx
Undergo CT
Also known as: CAT, CAT Scan, Computed Axial Tomography, Computerized Axial Tomography, Computerized axial tomography (procedure), Computerized Tomography, Computerized Tomography (CT) scan, CT, CT Scan, Diagnostic CAT Scan, Diagnostic CAT Scan Service Type, tomography
Ancillary studies
Undergo MRI
Also known as: Magnetic Resonance, Magnetic Resonance Imaging (MRI), Magnetic resonance imaging (procedure), Magnetic Resonance Imaging Scan, Medical Imaging, Magnetic Resonance / Nuclear Magnetic Resonance, MR, MR Imaging, MRI, MRI Scan, MRIs, NMR Imaging, NMRI, Nuclear Magnetic Resonance Imaging, sMRI, Structural MRI
Undergo MR-guided SBRT
Also known as: Magnetic Resonance Imaging-guided Stereotactic Body Radiation Therapy, MR-guided SBRT, MRI-guided SBRT
Ancillary studies
Incidence of grade ≥ 3 treatment-related toxicity
Safety defined as patients completing focal magnetic resonance (MR)-guided stereotactic body radiation therapy (SBRT) without grade ≥ 3 treatment-related toxicity (per Common Terminology Criteria for Adverse Events \[CTCAE\] version \[v\] 6.0) occurring within 90 days post treatment. Will be estimated along with its associated 95% Clopper Pearson exact binomial confidence interval (CI).
Time frame: Up to 90 days post-treatment
Incidence of all grades and grade ≥ 2 toxicities at least possibly related to study therapy
Tolerability of focal MR-Guided SBRT, defined as rate of all-grades and grade ≥ 2 toxicities at least possibly related to study therapy as measured by CTCAE v6.0. Will be summarized descriptively. Toxicities will be further categorized by timing (acute: ≤ 90 days post SBRT; late: 91 days to 1 year post SBRT) and by organ system, specifically genitourinary and gastrointestinal.
Time frame: Up to 90 days post-treatment
Change in urinary, bowel, and sexual function
Measured using the Expanded Prostate Cancer Index Composite-26 questionnaire. Will be summarized descriptively at each scheduled assessment time point among participants with available data.
Time frame: Baseline to 12 months post-treatment
Change in prostate symptoms
Measured using the International Prostate Symptom Score questionnaire. Will be summarized descriptively at each scheduled assessment time point among participants with available data.
Time frame: Baseline to 12 months post-treatment
Change in sexual health
Measured using the Sexual Health Inventory for Men. Will be summarized descriptively at each scheduled assessment time point among participants with available data.
Time frame: Baseline to 12 months post-treatment
Rate of biochemical recurrence
Defined as the proportion of patients experiencing an increase in prostate-specific antigen ≥ 2ng/mL above post-SBRT nadir. Will be summarized descriptively in the efficacy population, using proportions with corresponding CIs, consistent with the methods used for the primary endpoint.
Time frame: Up to 5 years
Rate of prostate in-field recurrence
Defined as the proportion of patients experiencing persistent or recurrent biopsy proven cancer in the treatment field. Will be summarized descriptively in the efficacy population, using proportions with corresponding CIs, consistent with the methods used for the primary endpoint.
Time frame: Up to 5 years
Rate of prostate out-of-field recurrence
Defined as the proportion of patients experiencing persistent or recurrent biopsy proven cancer in the prostate out-of-field. Will be summarized descriptively in the efficacy population, using proportions with corresponding CIs, consistent with the methods used for the primary endpoint.
Time frame: Up to 5 years
Rate of salvage therapy
Defined as the proportion of patients receiving salvage therapy (prostatectomy, additional radiation therapy, androgen deprivation therapy) after SBRT. Will be summarized descriptively in the efficacy population, using proportions with corresponding CIs, consistent with the methods used for the primary endpoint.
Time frame: Up to 5 years
Time to local radiographic progression
Will be estimated using Kaplan-Meier methods, along with their corresponding 95% CIs using log log transformation with Greenwood's estimator of variance. Death without prior progression will be treated as a competing risk, and cumulative incidence functions will be estimated accordingly.
Time frame: From initiation of SBRT to the first local radiographic progression in treatment field and remaining prostate, assessed up to 5 years
Time to distant radiographic progression
Will be estimated using Kaplan-Meier methods, along with their corresponding 95% CIs using log log transformation with Greenwood's estimator of variance. Death without prior progression will be treated as a competing risk, and cumulative incidence functions will be estimated accordingly.
Time frame: From initiation of SBRT to the first distant/metastatic radiographic progression, assessed up to 5 years
This study is not yet recruiting, as verified in Aug 2026. You cannot join it, but the record below documents what was studied.
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City of Hope Medical Center