- AI
- Molecular Imaging
- CT
- X-Ray
- Ultrasound
- MRI
- Facility Management
- Mammography
Emerging Perspectives on PSMA PET Radiotracers: An Interview with Kenneth J. Pienta, MD
In a recent interview, Kenneth J. Pienta, M.D., discussed the impact of piflufolastat F18, current directions in research with other PSMA-targeted radiotracers and future possibilities for the role of PSMA PET in the imaging paradigm for prostate cancer.
What kind of impact have clinicians seen with the use of piflufolastat F18 in detecting biomechanical recurrence of prostate cancer (PCa)?
Where is the research headed with PSMA conjugated radioligands?
What kind of impact will alpha particles have with newer agents?
Kenneth J. Pienta, M.D., director of research at the James Buchanan Brady Urological Institute and a professor of urology and oncology at Johns Hopkins School of Medicine in Baltimore, discussed these topics and more in a recent interview.
(This article has been adapted with permission from its original publication with our sister publication Urology Times.)
Q:Piflufolastat F 18 was approved in 2021. Could you touch on the significance of the FDA approval and where we are now with this agent?
I certainly was very pleased to be part of the clinical trials and the initial work to demonstrate the ability of piflufolastat F 18 (Pylarify, Lantheus) to detect prostate cancer, especially metastatic prostate cancer in the lymph nodes and bones. The approval of piflufolastat F 18 has allowed us to do some amazing work in understanding how prostate cancer spreads over time, helping us identify men at high-risk for having locally advanced prostate cancer, prostate cancer in the lymph nodes, at the time of primary treatment. That is something we want to know so that we can either do a better surgery or refer the patients to radiation for primary therapy because their disease has escaped the gland.
Biochemical recurrence happens in too many men. Previously, before piflufolastat F 18, we had to treat those patients empirically, not knowing where their disease was, or we had to wait until their disease manifested sometimes years after their PSA started to go up. Piflufolastat F 18 has allowed us to identify where that cancer is in those men with biochemical recurrence much sooner. That has allowed us to direct therapy appropriately, whether that's salvage radiation, hormonal therapy, or specific stereotactic radiation to say a lymph node or a bone metastasis.
Q: Can you discuss any ongoing research with F-18 targeted theranostics?
There are multiple agents in development for the therapeutic application of PSMA conjugated radioligands. Once you have a positive scan and metastatic disease, the question is: what happens to patients after 177Lu-PSMA-617? In the castrate-resistant setting, what else can they do? Well, there are multiple trials moving 177Lu-PSMA-617 up as a therapy. Should we be treating patients in the castrate-sensitive setting? Should we be treating patients who have oligometastatic disease with systemic 177Lu-PSMA-617 therapy? Those trials are ongoing.
Then there are multiple new agents that continue to be investigated (in comparison with) 177Lu-PSMA-617. Many of the alpha particles will continue to be looked at. For example, lead and thorium. We're going to have to see what the (adverse) effects of those newer agents are compared to say actinium versus lutetium. We know that the beta particles like lutetium have less (adverse) effects but are probably less efficacious. There's a balancing act with decreasing systemic toxicity around the alpha particles. There are also trials ongoing to try and mitigate the (adverse) effects of, for example, salivary gland dryness or renal damage, by using various protective agents. Those trials are also ongoing.
Q: How has PSMA PET imaging impacted the diagnosis and management of prostate cancer in clinical practice?
PSMA imaging is impacting therapy in three types of patients. Number one, the patient who, at the time of biopsy has high-grade prostate cancer, and we want to do PSMA imaging to understand who has cancer that has already escaped the gland, and we need to modify their curative therapy with either better surgery or potentially changed radiation fields. The second place that PSMA imaging has impacted the field is in the setting of biochemical recurrence, where we can direct therapy appropriately once we see (the location of the) disease. We can do that much sooner now, maybe months to years before regular imaging would ever detect that cancer. The third place that PSMA imaging is impacting the field is to identify patients who are eligible for treatment with drugs like 177Lu-PSMA-617 (Pluvicto, Novartis), the radioligand-directed therapy. You have to have a positive PSMA scan to be able to get that therapy appropriately.
Q: Could you discuss the significance of using a multidisciplinary approach with PSMA-PET imaging?
The advance of PSMA imaging has put an emphasis on multidisciplinary care. We now have a new imaging agent that identifies cancer that has spread outside of the prostate or is now oligometastatic. Now we are seeing, for example, therapy that requires surgery to take out the primary prostate, but potentially radiation also with it for an oligometastatic disease patient. Then you have to put into the mix, "Well, how do you do hormonal therapy and chemotherapy in that setting?" All of a sudden, we're seeing the use of nuclear medicine and radiology driving decision-making that involves urologists, radiation oncologists, and medical oncologists.
Q: Where do you see the PSMA-PET imaging paradigm in prostate cancer advancing to in the next 5 to 10 years?
I think what we're going to see over the next 5 to 10 years with PSMA imaging is to understand if identifying the cancer earlier changes outcomes. Or is it just an example of lead time bias in that we've identified the cancer earlier and we have to treat it. By treating it earlier, did we cure more people, or did we simply treat them longer and they're all now cured and living the same amount of time? That's going to be the great question over the next five to 10 years and what most academic folks who think about PSMA imaging and its impact on the field are wondering about.
Study Reaffirms Low Risk for csPCa with Biopsy Omission After Negative Prostate MRI
December 19th 2024In a new study involving nearly 600 biopsy-naïve men, researchers found that only 4 percent of those with negative prostate MRI had clinically significant prostate cancer after three years of active monitoring.
Can AI Enhance PET/MRI Assessment for Extraprostatic Tumor Extension in Patients with PCa?
December 17th 2024The use of an adjunctive machine learning model led to 17 and 21 percent improvements in the AUC and sensitivity rate, respectively, for PET/MRI in diagnosing extraprostatic tumor extension in patients with primary prostate cancer.
Assessing MACE Risk in Women: Can an Emerging Model with SPECT MPI Imaging Have an Impact?
December 9th 2024In research involving over 2,200 women who had SPECT MPI exams, researchers found that those who had a high score with the COronary Risk Score in WOmen (CORSWO) model had a greater than fourfold higher risk of major adverse coronary events (MACE).
New Study Examines Agreement Between Radiologists and Referring Clinicians on Follow-Up Imaging
November 18th 2024Agreement on follow-up imaging was 41 percent more likely with recommendations by thoracic radiologists and 36 percent less likely on recommendations for follow-up nuclear imaging, according to new research.
What SPECT/CT May Reveal About Early Treatment Response for Pluvicto in Patients with mCRPC
November 13th 2024Researchers found that new prostate lesion detection on SPECT/CT at the beginning of a second cycle of 177 Lu-PSMA-617 for mCRPC was associated with an over sevenfold higher mortality risk.
