I stumbled across this page/video, PSMA PET/CT- Struggling with Increased Sensitivity, of a presentation about bringing Ga 68 PSMA PET/CT imaging online from the Society of Nuclear Medicine and Molecular Imaging (SNMMI) Annual Meeting. It’s definitely worth the 23 minutes to watch it if you have any interest in imaging for prostate cancer.
Ga 68 PSMA PET/CT scans definitely can see much more than current imaging technologies and is fast becoming the new “gold standard” of prostate cancer imaging. But, as with anything new, there are things we have to understand to use the technology to its full advantage and to not misinterpret what it’s telling us.
One of the statements in the presentation that struck me was, “Just because you can see it, doesn’t mean you should treat it.” The presenter described the following scenario:
“So this is a patient who’s eight years after a prostatectomy with rising PSA and when the gallium PSMA PET scan is done, we see focal intense uptake in a solitary mesorectal node, which measures two to three millimeters and we’re really seeing micro metastatic disease. And I think the title of the slide is just because you can see it, doesn’t mean you should treat it because we don’t know how long that lymph nodes been there for. This is not in the classical nodal dissection. This lymph node could have been there five years ago and maybe it hasn’t changed and we don’t know that. So it’s easy now to say let’s cut it out because we can see it or let’s give it stereotactic radiotherapy, but I look at an image like this and think if it’s taken eight years for this lymph node to get to two to three millimeters, this is extremely indolent disease and perhaps it’s best left alone.”
He also talked about early interventions taken as a result of the PSMA PET/CT scans that may have caused more problems for the patient than necessary without changing the outcome (i.e., continued recurrence after the procedure).
Again, I found this to be very enlightening as I’m heading into my appointment this week and considering going to UCLA for their PSMA trial.