October 26, 2016
The Best Radiology Image in this year's Minnies awards, recognizing excellence in radiology, examines two new PET radiotracers, gallium-68 PSMA-11 and gallium-68 RM2, to determine their effectiveness in identifying rising levels of prostate-specific antigen (PSA), which signals prostate cancer recurrence. Existing imaging modalities such as CT, ultrasound, and MRI are already used to determine prostate cancer recurrence, but they have limited sensitivity and specificity.
The winning image was associated with a paper titled “Pilot Comparison of 68Ga-RM2 PET and 68Ga-PSMA-11 PET in Patients with Biochemically Recurrent Prostate Cancer,” which was published in the April 2016 issue of The Journal of Nuclear Medicine. The actual figure was shown at the 2016 SNMMI Annual Meeting and included in the highlights lecture.
Researchers at Stanford University, led by Andrei Iagaru, MD, FACNM, senior author and chief of the division of nuclear medicine and molecular imaging at Stanford, pointed out that the two agents target different biological processes and have different distribution patterns in the body. Some patients might benefit from having both scans performed, however. In addition, the agents could be labeled with lutetium-177 for therapeutic uses.
Neither of the gallium-68 agents have been approved yet by the U.S. Food and Drug Administration (FDA). The radiotracers cannot be used clinically until approved by the FDA.
Upon receiving word of the award, Iagaru said, "The Stanford team wants to acknowledge the efforts and support of the Clinical Trials Network at SNMMI, nuclear medicine colleagues in Heidelberg, Munich, Bologna, Melbourne, and São Paulo, and at UCSF, UCLA, MSKCC and Mayo, as well as many others worldwide who work together to bring new PET agents to their patients. This award is a recognition of the hard work of the entire nuclear medicine community."
Images are of an 83-year-old man with biochemically recurrent prostate cancer based on PSA levels. Images at far right are positive gallium-68 PSMA-11 and gallium-68 RM2 PET scans, both showing retroperitoneal lymph nodes while other studies are negative.