PSMA PET/CT superior to MRI for locoregional staging of prostate cancer, claims JAMA study

Prostate-specific membrane antigen (PSMA) is known for its overexpression in prostate cancer cells, making it a valuable target for imaging modalities like positron emission tomography (PET). While PSMA PET has been established as superior for metastatic staging, its efficacy in locoregional staging with second-generation radioligands like 18F-PSMA-1007 has been less studied.

The Next Generation Trial enrolled 150 men with intermediate-risk or high-risk prostate cancer, who underwent both 18F-PSMA-1007 PET/CT and MRI prior to radical prostatectomy. The study, conducted across two tertiary care hospitals in Alberta, Canada, analyzed data from 134 patients who completed the surgery. Radiologists and pathologists were blinded to imaging results, using histopathology as the gold standard.

The study findings were as follows:

Among the participants, 18F-PSMA-1007 PET/CT demonstrated superiority over MRI in several key parameters:

• PSMA PET correctly identified the final pathological tumor stage in 61 patients (45%), compared to 38 patients (28%) by MRI.

• PSMA PET accurately identified the dominant nodule in 94% of cases, whereas MRI achieved 83% accuracy.

• PSMA PET correctly identified tumor laterality in 64% of cases and extracapsular extension in 75% of cases, both significantly higher than MRI.

• While PSMA PET showed a trend towards higher accuracy (91%) compared to MRI (85%), the difference was not statistically significant.

The study concludes that 18F-PSMA-1007 PET/CT offers superior accuracy in locoregional staging of prostate cancer compared to MRI, particularly in identifying tumor stage, dominant nodules, and extracapsular extension. These findings support the integration of PSMA PET/CT into the preoperative workflow for patients with intermediate-risk and high-risk prostate cancers. This advancement could lead to better treatment planning and outcomes for patients, potentially reducing the need for additional diagnostic procedures post-surgery.

Reference:

Mookerji, N., Pfanner, T., Hui, A., Huang, G., Albers, P., Mittal, R., Broomfield, S., Dean, L., St. Martin, B., Jacobsen, N.-E., Evans, H., Gao, Y., Hung, R., Abele, J., Dromparis, P., Lima, J. F., Bismar, T., Michelakis, E., Sutendra, G., … Kinnaird, A. (2024). Fluorine-18 prostate-specific membrane antigen–1007 PET/CT vs multiparametric MRI for locoregional staging of prostate cancer. JAMA Oncology. https://doi.org/10.1001/jamaoncol.2024.3196