PSMA PET/CT may improve recurrent prostate cancer detection

Article: https://medicalxpress.com/news/2022-09-psma-petct-imaging-prostate-cancer.html

Research shows PSMA PET/CT imaging changes management for close to 50% of prostate cancer patients

by Society of Nuclear Medicine and Molecular Imaging

Graphical Abstract: Patients with detectable PSA (0.2-2.0 ng/mL) post-prostatectomy considered for salvage radiotherapy undergoing

In prostate cancer patients experiencing recurrence following a radical prostatectomy, imaging with 18F-DCFPyL PSMA PET/CT has been shown to considerably improve detection of active disease as compared to imaging with CT alone. As reported in the September issue of the Journal of Nuclear Medicine, detailed PET/CT scans resulted in a change in treatment plans for nearly 50% of patients.

Prostate specific antigen (PSA) recurrence—defined as a PSA level higher than 0.2ng/mL—occurs in 20 to 50% of all radical prostatectomy cases. In more than half of these patients, subsequent treatment with salvage radiotherapy (most commonly to the prostate bed) results in five-year biochemical control.

“For those patients who are experiencing a recurrence, it’s important to determine exactly where the cancer has spread so that it can be treated effectively with salvage radiotherapy,” said Michael Ng, MBBS (Hons), FRANZCR, radiation oncologist at GenesisCare St Vincent’s Hospital in Melbourne, Australia. “We know that prostate specific membrane antigen (PSMA) radiotracers have increased sensitivity in the detection of prostate cancer compared to conventional imaging. In this study we assessed the management impact of a novel PSMA tracer, 18F-DCFPyL PSMA PET/CT, in patients being considered for salvage radiotherapy.”

This study included 100 patients presenting with a detectable PSA following radical prostatectomy. Following patient registration and prior to any imaging, radiation oncologists outlined each patient’s “original intent” treatment plan on a questionnaire. All patients then underwent diagnostic CT and 18F-DCFPyL PSMA PET/CT. The CT results were released first, and a second “post-CT intent” questionnaire was completed. Next, the 18F-DCFPyL PSMA PET/CT results were released and a final “post-PSMA intent” questionnaire was completed. Change in management was graded based on impact and defined as major, minor, or no change demonstrated.

18F-DCFPyL PSMA PET/CT detected disease in 46.9% of patients compared to 15.5% on diagnostic CT. Major changes in the treatment plan were more likely to occur after PSMA imaging (12.5%) than after CT imaging (3.2%), and moderate changes were noted in 31.3% of patients after PSMA imaging versus 13.7% after CT imaging. The most common changes were recommendations for additional treatment, such as elective pelvic radiation, nodal boost, or concurrent androgen deprivation therapy.

Follow-up data were available at 18 months for 59 of the individuals in the study. At that timepoint, 92.5% had a PSA of below 0.20ng/mL and 74.5% had an undetectable (less than 0.03ng/mL) PSA.

“This research is novel as utilization of PSMA PET/CT allows earlier detection of prostate cancer after radical prostatectomy. The prospective study carefully collected changes in decision making and tracked the impact on patient management with outcome data available in patients who underwent radiotherapy,” noted Dr. Ng. “The group of patients studied—all post-surgery without other confounding treatments (no prior radiotherapy and no prior drug therapy) with a low and focused PSA range between 0.2-2.0ng/mL— reflects a common management problem. The study’s results are timely and applicable for patients experiencing their first recurrence after prostate surgery.”

Dr. Rob’s comment

In this study, PSMA PET/CT detected a prostate cancer recurrence 46% of the time, compared to only 15% for regular CT scans.

Forms

Upon receiving your requisition INITIO staff will contact you via phone to gather your detailed medical history. They will fill out the appropriate intake package on your behalf. Upon your arrival at the clinic, you will be given the opportunity to review and make any necessary edits to your intake package before signing.

Alternatively, you may print the intake package at home, fill out the forms with your medical history and send it to us either through fax: (604) 678–9279 or via e-mail: info@initiomedical.ca. If you are sending us an intake package please ensure that your doctor has sent us a requisition.

As per the INITIO Medical Group Inc. cancellation policy, at the time of booking, we ask each patient to provide us with their credit card details. This information is used in the event that the patient cancels their appointment, or fails to attend their scheduled appointment.

Please note that no charges are made to the credit card on file, except in the event of an appointment cancellation or a failure to attend a scheduled appointment. All charges for the scan are made in person upon completion of the appointment, at which point the credit card authorization form will be shredded.

  • CT Scans
    Booking Fee: $50
    Cancellation Fee: $100
  • PET Amyloid Scans
    Booking Fee: $750
    Cancellation Fee: $2000
  • PET FDG Scans
    Booking Fee: $500
    Cancellation Fee: $1000
  • PET PSMA Scans
    Booking Fee: $500
    Cancellation Fee: $1000