Molecular Imaging and Therapy in Prostate Cancer

Gary Ulaner, MD, PhD, FACNM, is the Director of Molecular Imaging and Therapy at Hoag Family Cancer Institute, as well as a Clinical Professor of Radiology and Translational Genomics, Keck School of Medicine, University of Southern California.

Dr. Ulaner sat down with us to detail the current application and capabilities of molecular imaging in prostate cancer.

What is the current application and capabilities of molecular imaging in prostate cancer?

Dr. Ulaner: I think it is, the prostate cancer has become potentially the most successful application of molecular imaging and therapy to date. There are numerous already FDA approved molecular imaging agents, since these are keys that bind to a molecule called PSMA, or prostate specific membrane antigen. And this PSMA is expressed on greater than 98, 99% of prostate cancer cells. So we have a key that can hit this target, PSMA, which is present on virtually every prostate cancer cell.

Now, these keys are bound to isotopes that emit low level radiation. There’s a key built called Pylarify, which is bound to fluorine 18. And there is also another key, gallium 68 PSMA-11, in which the gallium 68 emits a positron. So we have these multiple keys that bind to the lock, the PSMA, and they emit positrons, which allow us to detect where the prostate cancer cells are throughout the whole body. And they are remarkably sensitive, and have revolutionized the imaging of patients with prostate cancer.

And then the next step, if we take the same or a very similar key that binds to PSMA, and now bind to it something that emits a beta or an alpha particle, you have something that can treat prostate cancer.

So the first FDA approved molecular therapy for prostate cancer is known as Lutathera, which is a PSMA 617, one of these keys that is bound to Lutetium-177, that emits a beta particle. And you have a remarkably successful therapy that you can administer into the patient’s vein. It searches out the PSMA on the prostate cancer cells, binds to it throughout the body, and kills cancer cells with great efficacy.

And then now, maybe the next step is beyond the Lutathera, the beta emitters. There are people working on alpha emitting keys to PSMA that are currently on clinical trials. So, the whole field of PSMA molecular imaging and therapy has just exploded with multiple FDA approved imaging agents, one FDA approved therapy agent, and a whole host of additional molecular imaging and therapy agents for prostate cancer in clinical trials.

View Dr. Ulaner’s comments on Safety and Efficacy of 177Lu-PSMA-617 as well as RLT-PSMA in Development.