Radiolabeled Gallium-68 (68Ga-PSMA) for PET/CT Imaging to Detect Prostate Cancer

Phase 2

Terminated

Brief Summary: The purpose of the study is to find out whether imaging of the prostate with a new molecule called 68Ga-PSMA can find prostate cancer. 68Ga-PSMA has been shown in a large number of patients to be useful to find recurring prostate cancer following initial cancer treatment. This study is performed to test 68Ga-PSMA whether it can be used to find prostate cancers that would be considered in need for treatment.

Detailed Description: In this study, two different imaging tests are being compared: a) 68Ga-PSMA Positron Emission Tomography (PET)/Computed Tomography (CT) and b) Magnetic Resonance Imaging (MRI) of the prostate gland. Participants already have received the MRI, and the results were either suspicious of or definitive for prostate cancer. Both tests (MRI and 68Ga-PSMA PET/CT) are expected to show tumor tissue when more aggressive, but one test could be more accurate than the other test.

Another important question is whether these imaging tests will perform as good or better than prostate biopsies in finding all prostate cancer lesions in need for treatment. If imaging would be comparable or better than biopsies, then imaging may be able to replace invasive biopsies for some indications in the future.

To investigate these questions, participants are asked to undergo a 68Ga-PSMA PET/CT before a planned prostate biopsy procedure. After the biopsy procedure is performed, investigators will compare the imaging results from 68Ga-PSMA with those from the MRI and determine which test is more accurate.

Recruitment & Eligibility

Inclusion Criteria

Recent MRI of the prostate has resulted in at least one lesion suspected to represent prostate cancer (reported by the Radiologist as PI-RADS 3, 4 or 5 lesion)
Treating physician has already indicated a need for a prostate biopsy procedure.
Known Gleason 6 or 7 prostate cancer OR rising PSA with either a) no prior biopsy or b) single or multiple negative prior biopsies.

Exclusion Criteria

Prostate biopsy within 12 weeks before enrollment
Acute prostatitis within the last 6 months
Current non-urologic bacterial infection requiring active treatment with antibiotics
Active other malignancy (except basal cell or squamous cell skin cancer) within the last 2 years
Body weight greater than 350 lbs (158 Kg)
Inability or unwillingness to receive a prostate biopsy procedure
Unable to lie flat, still, or tolerate a PET/CT scan
Unable to provide own consent
Concurrent severe and/or uncontrolled and/or unstable medical disease other than prostate cancer (e.g. poorly controlled diabetes, congestive heart failure, myocardial infarction within 6 months prior to study participation, unstable and uncontrolled hypertension, acute renal failure of any intensity, chronic renal or hepatic disease, severe pulmonary disease).

Arm && Interventions

Group	Intervention	Description
68Ga-PSMA	68Ga-PSMA	PET/CT imaging with 68Ga-PSMA

Primary Outcome Measures

Name	Time	Method
Comparison of Two Different Radiologic Imaging Techniques, Fusion PET/MRI and Standard MRI, With Histopathologic Reference Data From Prostate Biopsy	Up to ~4 weeks (after planned, standard-of-care biopsy).	Fusion PET/MRI is the combination of 68Ga-PSMA Positron Emission Tomography/Computed Tomography (PET/CT) plus Multiparametric MRI (mpMRI)-guided biopsy. Reference standard will be pathology-defined as targeted plus standard prostate biopsy, and prostatectomy, when available. The original intent was to determine the sensitivity and specificity of standard-of-care Multiparametric MRI (mpMRI) alone (using PI-RADS version 2) and fusion PET/MRI for the detection of primary Gleason ≥3+4 cancer, and to estimate the positive likelihood ratio (LR) of each. However, due to pandemic-related early closure of the study, enrollment was less than 15% of the enrolment goal necessary to achieve statistical power. Therefore, it is not possible to responsibly report the originally listed outcome measure of likelihood ratio. Instead, the results table displays the summary of collected imaging data, categorized by type of scan, in comparison to the reference standard histopathology.

Secondary Outcome Measures

Name	Time	Method
Adverse Events of 68Ga-PSMA Administration	24 hours post injection	Adverse events will be determined through clinical assessment and categorized by CTCAE 4.0.