Advances in PSMA-Targeted PET Imaging for Prostate Cancer - Episode 8

PSMA-PET Results Reporting and Interpretation

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Gary Ulaner, MD, PhD, FACNM provides practical advice for radiologists who are generating PSMA-PET imaging reports, as well as for the urologists who are interpreting PSMA-PET results.

Transcript:

Gary Ulaner, MD, PhD, FACNM: For the radiologists interpreting, there’s a learning curve with false positives and false negatives. Those first hundred scans or so can be daunting. Mistakes are made the first time you’re driving the car, as opposed to the one thousandth. When you’re instituting something new and having new people reading the studies, you’re more likely to have errors than in a more established institution.

Gerald Andriole, MD: Gary, just to follow up on that; I’ve seen some ambiguously and vaguely worded PSMA PET [prostate-specific membrane antigen-positron emission tomography] scan reports. Is there a movement for standardized reporting? How do you get your colleagues to do that, etc?

Gary Ulaner, MD, PhD, FACNM: There are 2 standard reference systems for reading PSMA PETs. I believe one was spearheaded at Johns Hopkins and the other in Germany. I would say they’re not as widely utilized as you may expect. Certainly, where they’re developed they are utilized, but there’s a lot of gray area. Speaking as a doctor who wasn’t in one of those 2 areas where they were developed, it is challenging. Every imaging study then has people develop these algorithms for reading scans. I’m going to fall back on my training at Memorial Sloan Kettering Cancer Center, which used a single lexicon for diagnostic certainty and applied it to virtually any type of scan in which they tried to standardize care. You want to say, how certain are you of something being cancer, or suspicious of something being cancer, or something probably being benign? Then I use that throughout all the different types of imaging modalities that I interpret. Then the people who read my studies become familiar with the lexicon I use. So they know, when I say something is consistent with a metastasis, I feel very confident in it. Whereas, when I’m saying something is probably a metastasis, you have to take it with a grain of salt.

Ashley Ross, MD, PhD: One other minor thing, as we implement, to talk to the folks that are out there that are in private practice: make sure that you can be on some sort of modified packs or easy packs where you can look at the scan yourself, too. Even though I’m not a radiologist, and three-quarter of us on this call don’t have that kind of training, you can look to see, is there a bone correlate in a sclerosis? How bright does this look versus the other? That can be modified. You can ask your radiologist, “Do you think this is a ganglion, or is it really a lymph node? I didn’t see any sclerosis. Is this an early met [metastasis]? Is it something else?” Because I love what Gary just said about doing a Likert [scale] or propensity thing for each lesion, or the whole scan. But we often don’t get that; sometimes we’ll get scans that don’t even have SUVs [standardized uptake values] written through it, and there’s a question about that utility, too.

Transcript edited for clarity.