(UroToday.com) Dr. Michael Daneshvar continued the afternoon plenary session with an excellent presentation on advanced prostate cancer imaging specifically Fluciclovine based PET scans. He began by going over conventional imaging used in the staging and surveillance of prostate cancer including CT scan, MRI, and bone scan. For conventional imaging, being able to detect recurrent or metastatic disease usually requires larger burden of disease and elevated PSA levels. The most important factor is the detection and localization of recurrence of prostate cancer following treatment. Fluciclovine has emerged as a molecular imaging agent indicated for PET scan and the first FDA approved agent for detecting prostate cancer recurrence. In 2018 it was incorporated into the NCCN guidelines for the treatment of prostate cancer. Fluciclovine is a synthetic animo acid derivative that is carried by amino acid transporters which are upregulated in cancer, specifically prostate cancer. It is not metabolized or incorporated into newly synthesized proteins. It has limited urinary activity and helps delineate lesions directly adjacent to the bladder.
Dr. Daneshvar highlighted a recent study by Bach-Gansmo et. al in 2017 in which patients at 4 clinical sites underwent Fluciclovine scans for biochemical recurrence. There was a high positivity of 67.7% in patients with 38.7% recurrence in the prostate bed and 32.6% recurrence in the lymph node regions. 26.2% patients had involvement outside the pelvis. As the PSA increased the sensitivity of the Fluciclovine PET scans increased with a high detection rate in the prostate bed. Another study by Andriole et al in 2018 (LOCATE trial) evaluated how Fluciclovine PET scans impacted the clinical outcomes of biochemical recurrence. 213 patients with BCR underwent F18 PET scan with a median PSA of 1.0 ng/mL with detection rate of 57%. Most lesions were detected in the prostate bed and lymph nodes. 59% of patients had a change in their clinical management after the F18 PET scan. Dr. Daneshvar then highlighted another study by Pernthaler et. al in 2019 looking at F18 PET scan vs PSMA PET scan in patients with BCR. 58 patients underwent both scans within a 9.4 day period. Both scans performed very similarly in regards to overall prostate cancer recurrent detection however the Axumin performed statistically significantly better than PSMA PET scan in the detection of local recurrence. Compared with the PSMA PET scan, the slow physiologic urinary excretion of F18 Fluciclovine resulted in better detection of local recurrence around the bladder. There was comparable detection of nodal and bony metastatic disease. The pros of F18 PET scan include better imaging than conventional imaging, advantages in locally advanced disease and ADT may not have an effect on its performance. Cons include no theranostics, like PSMA PET scan and sensitivity not as high as PSMA PET scan.
Dr. Daneshvar concluded that PET/CT with Axumin is beneficial for localization of recurrent prostate cancer. It can change clinical management in men with biochemical recurrence specifically localizing disease to the pelvis. It may possibly improve overall survival and reduce late-stage diagnosis. Both F18 PET scan and PSMA PET scan are complementary to each other with strengths in different areas.
Presented by: Michael Daneshvar, MD, MS, University of California, Irvine
Written by: Sohrab Naushad Ali, MD, MSc, FRCSC, Assistant Clinical Professor, Department of Urology, University of California Irvine, @sohrabnaushad on Twitter during the 39th World Congress of Endo urology and Uro-Technology (WCET), Oct 1 - 4, 2022, San Diego, California.