An Investigational Scan (rh PSMA 7.3 PET/MRI) for the Detection of Recurrent Disease and Aid in Radiotherapy Planning in Biochemically Recurrent Prostate Cancer

Overview

This prospective pilot study will assess the feasibility of rh PSMA 7.3 positron emission tomography/magnetic resonance imaging (PET/MRI) scans in detecting prostate cancer that may have come back (recurrent) in patients with increasing levels of prostate-specific antigen (PSA) following prostate surgery (biochemically recurrent). An increase in PSA levels alone does not tell the doctor where the cancer may be or how much cancer there may be. Imaging tests, like a bone scan, MRI, and/or computed tomography, are often performed to help the doctor learn where or how much cancer there is, and how best to treat the cancer. rhPSMA-7.3 is a radioactive tracer agent that when used with PET/MRI imaging may help diagnose and look for the spread of prostate cancer. Prostate-specific membrane antigen (PSMA) is a protein that is expressed in prostate cancer and this agent targets the PSMA molecule. Giving rh PSMA 7.3 during PET/MRI may help doctors better find where the cancer may be spreading and how much of it there is. The results of this trial may also guide in radiotherapy planning.

PRIMARY OBJECTIVE: I. To evaluate the positive predictive value and detection rate of fluorine F 18 rhPSMA-7.3 (F-18 rhPSMA-7.3) positron emission tomography (PET)/magnetic resonance imaging (MRI) in detecting recurrent disease in prostate cancer patients with biochemical recurrence. SECONDARY OBJECTIVE: I. To determine the change in salvage radiation treatment plan after F-18 rhPSMA-7.3 PET/MRI imaging. EXPLORATORY OBJECTIVES: I. To assess the feasibility of utilizing the PSMA avid recurrent disease on PET/MRI as an alignment tool for MR guided radiotherapy (MR linear accelerator \[MR-LINAC\]). II. To assess the treatment response in those patients who demonstrate rhPSMA-7.3 avid disease on the first PET/MRI scan. OUTLINE: Patients receive F-18 rhPSMA-7.3 intravenously (IV) and after approximately 60 minutes of uptake time, will undergo PET/MRI over 60 minutes. Patients with evidence of F-18 rhPSMA-7.3 disease in the first PET/MRI scan undergo a second F-18 rhPSMA-7.3 PET/MRI at 6 months after the second dose of standard hormonal therapy. After completion of study treatment, patients are followed up within 7 days.