Another study confirms 68Ga-PSMA-11 PET’s important role in prostate cancer care

A team of California-based researchers found Gallium-68-labeled PSMA-11 PET highly sensitive and accurate at detecting cancer metastases in patients with biochemically recurrent prostate cancer.

The prospective single-center study, published April 30 in the American Journal of Roentgenology, adds more weight to the growing literature suggesting PSMA-11’s vital role in prostate cancer management.

In the current study, researchers examined the diagnostic accuracy of 68Ga-PSMA-11 PET in 150 patients who underwent imaging with the radiotracer or PET/MRI. Two board-certified radiologists evaluated the images for the presence or absence of PSMA-positive diseases within the prostate bed, pelvic lymph nodes, bones and soft tissue.

A cancer diagnosis was confirmed by histopathologic analysis when available. Otherwise, the researchers used a composite of imaging and clinical follow-up.

Overall, 68Ga-PSMA-11 PET had an up to 100% sensitivity per region and a high sensitivity per patient (up to 89.8%). Positive predictive value was high per region and per patient achieving up to 100% and up to 91.5%, respectively. Positive predictive value was also high per region and per patient.

The team did find low specificity and negative predictive values for PSMA-11.

Importantly, the authors noted 68Ga-PSMA-11 PET had a nearly “perfect” interreader reliability by region with kappa scores ranging from 0.78-0.87.

The high scores were similar to those in a 2017 multicenter study that only included experienced readers, the authors noted, unlike their current study which included both experienced and inexperienced readers.

Courtney Lawhn-Heath, MD, of the department of radiology and biomedical imaging at the University of California-San Francisco, and colleagues found their results, along with past studies, cement PSMA PET’s central role in prostate cancer care.

“Our prospective study complements the existing literature, including several retrospective studies showing high sensitivity and accuracy for the detection of recurrent disease in patients with biochemical recurrence of prostate cancer,” the authors concluded. “Taken together with those of prior studies, our prospective results confirm high sensitivity and accuracy of PSMA PET in this population and suggest an important role for this modality in guiding prostate cancer management in the future.”