Targeted Fusion Biopsy of the Prostate

The purpose of this study is to see if using Positron Emission Tomography (PET) scan and transrectal ultrasound (TRUS) guided biopsy together (creating a 3-dimensional ultrasound) will detect prostate cancer more accurately than the standard 2-dimensional approach which uses only the TRUS to guide the biopsy.

The objective of the proposed study is to evaluate a molecular image directed, three-dimensional (3D) ultrasound guided biopsy system in human patients. Prior studies have shown that Positron Emission Tomography (PET)/Computed Tomography (CT) imaging with the PET molecular imaging agent, a synthetic amino acid, anti-1-amino-3-[18F]fluorocyclobutane-1- carboxylic acid (FACBC), is more sensitive than the FDA-approved prostate specific membrane antigen single-photon emission computed tomography (SPECT) radiotracer in prostate cancer detection. FACBC images showed higher focal uptake in tumor foci than in normal prostate and thus could be ideal information to direct targeted biopsy of the prostate. This targeted biopsy system has a unique feature that PET/CT images can be registered with 3D ultrasound images, as a result, a suspicious PET lesion is superimposed over the real-time ultrasound data; and the fused image is then used to direct biopsy needles to tumor targets. The hypothesis of the study is that PET/ultrasound fusion targeted biopsy can detect more cancer per core than the standard 12-core TRUS guided biopsy. The specific aims include: To perform PET/CT directed, 3D ultrasound-guided biopsy and determine if fusion targeted biopsy can detect more cancers than 2D transrectal ultrasound (TRUS)-guided biopsy To develop the workflow for performing deformable registration and fusion of PET/CT and 3D ultrasound images of human patients Thirty six patients, who have suspicion of recurrent prostate cancer after definitive therapy such as radiotherapy, will be recruited into this study. At least half of the patients will have positive imaging findings and will undergo 2D TRUS-guided biopsy as well as PET/ultrasound fusion biopsy. The proposed study will be the first-in-human trial that uses PET/CT imaging to direct 3D ultrasound-guided biopsy of the prostate. The multimodality imaging approach will combine the high sensitivity from PET and real-time information from ultrasound for improved cancer detection.

All participants with suspected recurrence of prostate cancer will have the FACBC PET-CT scan performed. Participants with abnormal FACBC PET-CT scan results will have a PET/ultrasound fusion targeted prostate biopsy followed a standard of care prostate biopsy.

All participants with suspected recurrence of prostate cancer will have the FACBC PET-CT scan performed. Participants without abnormal FACBC PET-CT scan results will have a standard of care prostate biopsy.

One hour prior to scanning, participants will drink one glass (450 ml) of oral contrast to allow for better pictures of abdomen and pelvic organs. The participants will have their temperature taken before and after the injection of the FACBC. Blood pressure and pulse will be taken every 15 minutes during the PET scan. Participants will lie on a scanning bed and the bed will move slowly through the PET/CT scanner. This portion usually takes about one minute. Following this the FACBC will by administered by an intravenous (IV) catheter and the PET scan portion of the exam will begin. The table moves slowly through the scanner and many sets of PET-CT images are produced. When the imaging is complete, the scanner will send the results to a computer. The computer then generates a number of images that will be reviewed by a specially trained radiologist.

A lubricated rectal probe will be inserted and a local anesthetic to numb the prostate will be administered. The ultrasound probe allows visualization of the prostate in two-dimensional (2D) images. The probe connects to a computer that will link to the FACBC PET-CT scan results that the participant has already had performed. These combined images will provide a three-dimensional (3D) image from the FACBC PET-CT scan previously obtained as well as real-time, 2D ultrasound images, resulting in an improved visualization tool to target the biopsy needle to a suspicious lesion. The needle tip position for each biopsy sample will be recorded on the real-time ultrasound images; this information allows the physician to either re-biopsy the same area for a follow-up examination or not to re-biopsy the same region if the original biopsy was negative. This biopsy process is estimated to take about 10 minutes.

A lubricated ultrasound probe of about 2.5 cm in diameter is gently inserted into the rectum and a local anesthetic to numb the prostate is administered. The ultrasound probe allows visualization of the prostate in two-dimensional (2D) images and allows for the placement of a biopsy needle that collects samples of the prostate. Usually, a total of 12 biopsy specimens are collected. The procedure takes about 20 minutes. This TRUS-guided biopsy is considered as the standard method for prostate cancer diagnosis.

The cancer detection rate per core was compared between the targeted prostate biopsy and standard of care prostate biopsy.

Inclusion Criteria: Have been originally diagnosed with prostate carcinoma and have undergone definitive non-prostatectomy therapy for localized disease There is suspicion of recurrent prostate carcinoma as defined by: Older American Society for Radiation Oncology (ASTRO) criteria of three consecutive rises of prostate-specific antigen (PSA) or earlier if clinically appropriate, and/or nadir + 2.0 ng/ml (Radiation Therapy Oncology Group (RTOG)-ASTRO Phoenix criteria) Able to provide written informed consent Exclusion Criteria: Cryotherapy, external beam radiation, or high intensity focused ultrasound (HIFU) within the past year Brachytherapy within the past two years (to rule out a transient rise in PSA) Prostate biopsy within the past month (to decrease a false positive result due to inflammation) Not otherwise eligible for prostate biopsy