A Pilot Study of [Ga-68]PSMA PET/MRI for the Assessment of PSMA-positive Tumors

Primary Objective

The primary objective of this pilot imaging study is to determine the feasibility of using
positron emission tomography/ magnetic resonance (PET/MR) with [Ga-68] prostate-specific
membrane antigen (PSMA) for staging and treatment monitoring of PSMA expressing tumors.
[Ga-68]PSMA PET/MR findings will be compared with standard of care imaging, patient follow
up, and histopathology if available. [Ga-68]PSMA PET/MR will not be used to change the
patients' treatment plan. Investigators will assess PET/MR test-retest reproducibility and
compare baseline [Ga-68]PSMA PET/MR with PET/MR after initiation (within 2-6 weeks) of
therapy and evaluate if [Ga-68]PSMA is a suitable biomarker for treatment monitoring and
assessment of early treatment response.

Secondary Objectives

- To compare early changes in PET biomarker ([Ga-68]PSMA) tumor uptake with treatment
response assessed at completion of therapy (prediction of treatment response).

- To compare changes in MRI signal intensities (multi-parametric MRI) with treatment
response assessed at completion of therapy.

- To compare results from multi-parametric MR imaging with [Ga-68]PSMA uptake.

- To assess combinations of quantitative PET and MRI metrics.

Study Design Patients, who enroll in this study, will undergo a baseline [Ga-68]PSMA PET/MR
to assess the level of [Ga-68]PSMA tumor uptake. Patients with positive [Ga-68]PSMA tumor
uptake (defined as [Ga-68]PSMA uptake twice the background activity) who are receiving
systemic therapy will undergo a further [Ga-68]PSMA PET/MR 2-6 weeks after start of
treatment. Patients with positive [Ga-68]PSMA tumor uptake will also be offered to
participate in a test- retest study with a 2nd [Ga-68]PSMA PET/MR prior to treatment.
Patients will therefore undergo a maximum of three [Ga-68]PSMA PET/MR imaging procedures. The
first two test-retest Ga-PSMA-PET/MRI will be performed on separate days to allow for
radioactive decay. There will be no other (e.g. clinically indicated) PET scan performed on
the same day of [Ga-68]PSMA-PET/MRI.

Inclusion Criteria:

- Patients with PSMA-positive tumors including prostate cancer, breast cancer, lung
cancer, and other tumor types know to express PSMA

- Patients able to tolerate PET/MRI scans

- Informed consent must be given and signed

Exclusion Criteria:

- Subjects who do not meet the above mentioned inclusion criteria

- Subjects who refuse to give and/or sign the informed consent

- Patients who have a history of serious adverse events related to a previous MRI or
PET/CT

- Patients who are unable to undergo MRI scanning due to exclusion by institutional MRI
restriction policies as mentioned in the standard institutional MRI informed consent
form

- Patients who are currently pregnant or breast feeding. A pregnancy test within 72
hours of the first PET/MRI will be performed.

- Anti-cancer treatment (chemotherapy and/or radiation therapy) within the last 2 weeks.

- Renal insufficiency: elevated Creatinine and/or Glomerular Filtration Rate
(GFR)<40ml/min/1.7sqm (exclusion criterion only for contrast enhanced MRI)

- Patients with a known allergy against any component of the contrast enhancing MR agent
will not receive MR contrast agents. (exclusion criterion only for contrast enhanced
MRI)