In a main study involving medical records from 115 men, PET scans with Axumin correctly detected cancers in 99% of all patients whose cancer had in fact returned (as confirmed by tissue sampling). When the scans from this study were looked at by another team of researchers, the scans were again shown to be able to detect cancer in most patients who had it. (87% of patients with cancer had positive scans.)

However, because some scans with Axumin were falsely positive (showing that cancer had returned when tissue sampling was negative), a positive result on its own is not enough to make a diagnosis. Depending on the person reading the scans, only 17 to 54% of patients whose tissue samples did not show cancer had a negative scan result.

All men enrolled in this study had already shown some signs that the cancer might have returned, such as increases in blood levels of PSA, a protein produced in the prostate glands. The accuracy of the scans varied depending on the PSA levels.