A review of available PSMA PET tracers for prostate cancer detection, covering sensitivity, specificity, access to therapy, and reimbursement impacting patient care.
Naveen Kella, MD: Would you discuss the clinical data on the accuracy of prostate cancer detection for these PSMA PET tracer options? How often are radiologists saying these are indeterminate on scans? And…are you seeing similarities between the way they set up these studies for the different tracers?
Shadi Abdar Esfahani, MD, MPH: I would say right now, both of these gallium 68–labeled and fluorine 18 [F18]–labeled compounds are being used in different institutions across the US and also worldwide. The only problem is that…they are very, very similar in terms of their ability and their detection rate, but there haven’t been a lot of head-to-head comparisons of the same compounds in the same patient to exactly answer that question. Obviously they both function very, very well in terms of their ability to detect the sites of disease and their sensitivity and also their specificity compared with conventional imaging modalities…. And then the second part of this discussion [is] if one functions better than the other, [and] it’s a little bit tough, again, to say because there are not a lot of data on the same patient populations. But in general, they function very similarly.
There is a study that was done in 2020, and in that head-to-head comparison, it was thought that…in the F18 compounds, because of the nature of the fluorine 18 and the fact that it can get dissociated from the major compound and because of the nature of the F18 that can get absorbed in the bone, there may be higher background bone uptake or there may be more of the benign lesions that could have uptake. Or we would have to read them as either benign or indeterminate and then go further, evaluate them to see if they’re benign or if they are malignant. But again, the data are very, very sparse in that space of head-to-head comparison.
But obviously both of them function very well. Right now the major challenge for us is that if the patient requires…[lutetium 177] treatment and is specifically getting the PSMA PET for that indication, CMS [Centers for Medicare & Medicaid Services] is approving the gallium 68 compound. And that might be a major challenge for us given that with the gallium 68, we would need to have either a generator in house or we would need to have great suppliers around us. Obviously, if we could have the reimbursement for both of these, then it would have been much easier for our patients and also for the radiologists and for the oncologists to have greater accessibility to treat the patients in a timely manner and avoid any kind of delay.
Naveen Kella, MD: Great. It’s really informative.
Transcript is AI-generated and edited for clarity and readability.