NCT05155046 · National Cancer Institute (NCI)
18F-DCFPyL Imaging as a Method to Assess Treatment Response to Stereotactic Body Radiation Therapy
What this study is about
Background: Identifying medium- and high-risk prostate cancer early may allow for treatments to work. But identification can be hard. Researchers want to see if a radiotracer used during PET scans can help. Objective: To test how an imaging agent called 18F-DCFPyL detects response to standard prostate cancer treatment.
View original scientific description
Background: Identifying medium- and high-risk prostate cancer early may allow for treatments to work. But identification can be hard. Researchers want to see if a radiotracer used during PET scans can help. Objective: To test how an imaging agent called 18F-DCFPyL detects response to standard prostate cancer treatment. Eligibility: People ages 18 and older with newly diagnosed prostate cancer who have no evidence of distant metastatic disease and plan to get stereotactic body radiation therapy (SBRT) with or without androgen deprivation therapy (ADT). Design: Participants will be screened with: Medical history Physical exam Blood tests MRI Participants will have baseline MRI and PET/CT scans. For the MRI, they may get a contrast agent by IV injection. For the PET/CT scan, they will get an IV injection of 18FDCFPyL. About 1 to 2 hours later, they will get the PET/CT scan. During the scans, participants will lie on their back and remain still for 45 minutes to 1 hour. These scans will be repeated at different points during the study. Participants will get SBRT with or without ADT. Participants will complete questionnaires about their quality of life. Participants will be asked about any symptoms they are having. They will also be asked about medications they are using. They may have a physical exam. Participants will give blood and urine samples. They will give a tumor sample from a biopsy they have had in the past. After treatment, participants will have follow-up visits. These will occur 1 month after treatment, then every 3 months for a year, and then every 6 months for 1 more year.
Interventions
DRUG
18F-DCFPyL
18F-DCFPyL imaging will be performed at baseline, 8 weeks after ADT initiation, 6 months post SBRT and at recurrence. The target administered activity will be 6.5 mCi with a lower limit of 6 mCi.
Primary outcome measures
Imaging response to treatment
Time frame: Baseline, 8 weeks after ADT initiation (if applicable), 6 months post SBRT, at recurrence
For the purpose of this study, the imaging response to treatment will be categorized separately in the radiation treatment volume (in field; local) and distantly (outside the radiation treatment volume). In-field (in the radiation target volume) 18F-DCFPyL PET/CT treatment response in field will be evaluated using a descriptor (complete, partial, progression) based on maximum SUV and volume of uptake relative to the pre-treatment imaging. Presence of new areas of uptake suspicious for prostate cancer outside of the region of radiation treatment will be considered progression but will be scored separately and will not impact the assessment of response from radiation locally.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Biopsy proven localized prostate cancer in whom stereotactic body radiation treatment (SBRT) with or without neoadjuvant androgen deprivation therapy (ADT) is planned for definitive management (NIH laboratory of pathology confirmation is not required).
- Must have at least 1 MRI detected, biopsy proven localized prostate cancer.
- Age \>= 18 years
- ECOG performance status \<= 2
- For individuals with evidence of human immunodeficiency virus (HIV) infection, individuals must be on effective anti-retroviral therapy with undetectable viral load within the prior 6 months are eligible.
- For individuals with evidence of chronic hepatitis B virus (HBV) infection, the HBV viral load must be undetectable on suppressive therapy, if indicated.
- For individuals with a history of hepatitis C virus (HCV), the infection must have been treated and cured. For individuals with HCV infection who are currently on treatment, they are eligible if they have an undetectable HCV viral load.
- Ability of subject to understand and the willingness to sign a written informed consent document.
- Men must agree to use adequate contraception with their partner (hormonal or barrier method of birth control; abstinence) for the duration of study participation and 2 months after the last 18F-DCFPyL scan.
Exclusion criteria
- Receiving prior androgen deprivation therapy, radiotherapy, or surgery for prostate cancer.
- Any condition that is likely to interfere with study procedures or results.
- Individuals in whom pelvic nodal irradiation is planned.
- Serum creatinine \> 2 times the upper limit of normal.
- Weighing \> 350 lbs (weight limit for scanner table), or unable to fit in imaging gantry.
- Evidence of tumor spread beyond the prostate/seminal vesicles (lymph nodes, metastases).
- Contraindications to radiation or SBRT.
Where
- Bethesda, Maryland
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
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Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
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Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
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Data: ClinicalTrials.gov · synced Jul 16, 2026 · Source of record for eligibility and locations