Biomarker Monitoring of Prostate Cancer Patients With RSI MRI (ProsRSI)

NCT04349501 | Active Not Recruiting

• 1 other identifier: 200266
• Study Type: interventional
• Target: 100
• Locations: 1 country
• Sites: 1

Brief Summary

Adult male patients with high-risk, localized prostate cancer and planning to undergo radiation therapy (RT) with androgen deprivation therapy (ADT) will undergo an advanced Magnetic Resonance Imaging (MRI) examination called Restriction Spectrum Imaging (RSI-MRI) to evaluate whether RSI-MRI can predict treatment response.

Conditions

Prostate Cancer

Outcome Measures

Primary Outcomes (1)

• Biochemical recurrence (PSA 2 ng/mL greater than nadir) within 3 years of completing RT.

  To evaluate the performance of the RSI cellularity index before and during therapy as a biomarker to identify participants who will experience biochemical recurrence within 3 years post-radiotherapy.

  within 3 years of RT completion

Secondary Outcomes (1)

• PSA nadir within the 18 months after RT ≥0.5 ng/mL.

  within 18 months of RT completion

Study Arms (1)

RSI-MRI

EXPERIMENTAL

Participants will undergo RSI-MRI at three time points: before androgen deprivation therapy (ADT); after neoadjuvant ADT but before radiation therapy (RT); and after RT.

Other: Restriction Spectrum Imaging Magnetic Resonance Imaging

Interventions

Restriction Spectrum Imaging Magnetic Resonance Imaging OTHER

RSI is a multicompartment model of diffusion MRI that uses data acquired at multiple b-values to distinguish varied diffusion speeds (restricted intracellular, hindered extracellular, and approximately free diffusion).

Also known as: RSI-MRI

RSI-MRI

Eligibility Criteria

• Age: 18 Years+
• Gender Eligibility Details: Male subjects undergoing treatment for Prostate Cancer
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Male, aged ≥18 years, with histologically confirmed adenocarcinoma of the prostate
• High-risk prostate cancer (any of: PSA ≥20 ng/mL or cT3-T4 stage or Gleason score ≥8)
• Intended treatment and follow-up according to standard of care for prostate cancer
• Planning to undergo definitive radiotherapy with neoadjuvant and concurrent androgen deprivation therapy
• In good general health as evidenced by medical history and Eastern Cooperative Oncology Group (ECOG) performance status 0-2
• Provision of signed and dated informed consent form
• Stated willingness to comply with all study procedures and availability for the duration of the study

You may not qualify if:

• Prior radiotherapy to the pelvis
• Prior treatment for prostate cancer (cryotherapy, high frequency focused ultrasound, prostatectomy)
• Hip prosthesis
• Contraindication to MRI, per institutional requirements
• Technetium-99 bone scan showing no clear evidence of distant metastasis
• MRI or CT scan of the pelvis showing no clear evidence of bone or distant metastasis
• Another malignancy, unless in remission or unlikely to impact the patient's survival or ability to receive standard care for prostate cancer (e.g., cutaneous basal cell carcinoma)
• Patient has a history or current evidence of any condition, therapy, or laboratory abnormality that might confound the results of the trial, interfere with the subject's participation for the full duration of the trial, or is not in the best interest of the subject to participate, in the opinion of the treating investigator.

Sponsors & Collaborators

• University of California, San Diego: lead

Study Sites (1)

UCSD Moores Cancer Center

La Jolla, California, 92093, United States

Location

MeSH Terms

Conditions

Prostatic Neoplasms

Condition Hierarchy (Ancestors)

Genital Neoplasms, Male; Urogenital Neoplasms; Neoplasms by Site; Neoplasms; Genital Diseases, Male; Genital Diseases; Urogenital Diseases; Prostatic Diseases; Male Urogenital Diseases

Study Officials

• Tyler Seibert, MD, PhD

  University of California, San Diego

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: DIAGNOSTIC
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assistant Professor, Radiation Medicine and Applied Sciences

Model Details: A logistic regression model of biochemical recurrence within 3 years will be fit, using maximum likelihood, on the change in RSI cellularity index from MRI #1 to MRI #2 and relevant covariates such as demographics. Continuous variables will be splined; only main effects will be considered. The cross-validated Area Under the Curve (AUC) for this model will be reported with a 95% bootstrap confidence interval using Efron's bias-corrected and accelerated (bca) method. If the lower bound on the 95% confidence interval of the Area Under the Curve (AUC) excludes 0.55, RSI cellularity index will be declared "viable" for identifying participants who will recur within the three-year post treatment. If declared "viable", a Cox model for predicting recurrence time will be fit, and the hazard ratios for RSI will be used to describe the adjusted associations supported by the data between RSI cellularity index and recurrence time.

Study Record Dates

• First Submitted: April 14, 2020
• First Posted: April 16, 2020
• Study Start: December 29, 2020
• Primary Completion (Estimated): December 1, 2026
• Study Completion (Estimated): December 1, 2026
• Last Updated: November 5, 2025

Record last verified: 2025-11

Locations

US (1)