Hyperpolarized Imaging for Primary CNS Lymphoma

This study is looking at a new way to image primary central nervous system lymphoma (PCNSL), a type of brain cancer. It uses a special MRI (magnetic resonance imaging) scan after you receive an injection of hyperpolarized pyruvate (13C). Researchers want to see if this new imaging method is safe and helpful for detecting PCNSL and checking how well treatments are working. You might be able to join if you are 18 or older and have PCNSL that has come back (relapsed) and can be seen on a previous MRI scan. The main goals are to find out if this imaging method is safe, if it works well, and to figure out the best way to do the scans. The study aims to enroll 26 participants, but the current recruitment status is unclear.

Study design
This is an interventional study, meaning participants will receive a specific intervention. It plans to enroll 26 participants, but the phase is not specified.
What's involved
You would receive an intravenous (IV) injection of hyperpolarized pyruvate (13C) and then have an MRI scan of your brain and/or spinal cord, which takes up to 45 minutes.
Compensation
Not stated in the trial record.
Follow-up
Your safety will be checked for adverse events, vital sign changes, and injection site changes for 1 day after the intervention.

AI-generated from the public study record. Only the study team can confirm whether you're eligible — confirm details with them before making decisions.

NCT04656431

Feasibility of Acquiring Hyperpolarized Imaging in Patients With Primary CNS Lymphoma

Recruiting
PHASE1Ages 18+InterventionalDiagnostic
James Rubenstein
~26 participants
Updated 2026-07-14 on ClinicalTrials.gov
What's tested:Hyperpolarized pyruvate (13C)Magnetic resonance imaging (MRI)

At a glance

Recruiting sites
1 of 1 listed site is recruiting right now
RecruitingSuspended, closed, or not yet open
What they're measuring
Proportion of participants with treatment-emergent Adverse Events
Measured over 1 day
+7 more outcomes measured
Primary CNS Lymphoma

NCT04656431

Where you'd take part

This study runs at 1 site. They're the same protocol — you choose where, and that choice sets who your contact draft is addressed to.

  • University of California, San Francisco

    San Francisco, Californiastudy coordinator listed

    Recruiting

Sites open and close at different times, so the status above is per site — it can differ from the study's overall status.

  • James Rubenstein, MD, PhD · PRINCIPAL_INVESTIGATOR · University of California, San Francisco

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Eligibility criteria

Inclusion

For Patients in Cohort 1: Histologically proven relapsed PCNSL who have evidence of evaluable disease based on a prior MR scan, or relapsed CNS lymphoma: measurable disease based on MRI is defined as gadolinium enhancement of a CNS lymphoma lesion (at least one centimeter (cm) diameter).
For Patients in Cohort 2: Histologically proven newly diagnosed PCNSL who will receive standard treatment with high-dose methotrexate, temozolomide plus rituximab (MT-R). These criteria will ensure validity of this study in terms of safety, evaluation of clinically and radiographically relevant disease.
  • Proportion of participants with treatment-emergent Adverse Events1 day

    The Common Terminology Criteria for Adverse Events (NCI CTCAE version 5.0) will be used to classify and graded any adverse events that occur after the participant has received the hyperpolarized 13C injection.

  • Number of participants with abnormal changes in vital signs1 day

    Clinically significant changes in heart rate and blood pressure will be measured pre- and 10 minutes, 1 hour, 24 hours, and 48 hours post- injection as a measure of safety. The occurrence of changes from baseline, at each post-administration time point, greater than a pre-specified magnitude (20 mm Hg for systolic blood pressure, 10 mm Hg for diastolic blood pressure, 10 beats per minute for heart rate).

  • Number of participants with abnormal changes in injection site1 day

    Injection site will be monitored for evidence of inflammation or infection. Abnormal injection site findings include, but are not limited to, extravasation, bleeding, hematoma, redness, and infection as a measure of safety.

  • Percent of eligible patients that complete the studyUp to 4 months

    The percentage of participants whom complete the study will be used to determine feasibility with a goal of at least 50%

  • Pyruvate-to lactate conversion (kPL)1 day

    The kinetics of hyperpolarized \[1-13C\] pyruvate and 13C- in cancer models using a compressed sensing dynamic MRSI method

  • Number of participants with responseUp to 4 months

    Radiographic confirmed response with state-of-the-art MRI exam (including diffusion imaging, contrast-enhanced MRI and hydrogen magnetic resonance spectroscopic imaging (H1-MRSI) Determination of response status (complete response, partial response or stable disease) as standard will be made at 4 months after initiation of therapy

  • Signal Amplitudes1 day

    Hyperpolarization of 13C pyruvate, using dynamic nuclear polarization (DNP), enhances nuclear magnetic resonance (NMR) signals. The greater the amplitude of the signal, the larger the number of protons in the image and the brighter the signal will appear.

  • Time Dynamics1 day

    For the 2D dynamic data, the time resolution will be 3-5s. For the 3D single time point data the start time will be adjusted based upon when it is anticipated that the lactate/pyruvate will be at a maximum.