Comparison of 18F-DCFPyL and 68Ga-PSMA-11 for 177Lu-PSMA-617 therapy patient selection

Purpose: Ga-68-PSMA-11 is recommended for the selection of patients for treatment in the package insert for Lu-177-PSMA-617. We aimed to compare imaging properties and post-treatment outcomes from radioligand therapy (RLT) of patients selected with Ga-68-PSMA-11 and F-18-DCFPyL. Methods: We retrospectively evaluated 80 patients undergoing PSMA RLT, who had pretreatment imaging using either Ga-68-PSMA-11 or F-18-DCFPyL. For both groups, we compared the biodistribution and lesion uptake and the PSA response to treatment. Results: Both agents had comparable biodistribution. Patients initially imaged with F-18-DCFPyL had a higher PSA response (66% vs. 42%), and more patients had a PSA50 response (72% vs. 43%) compared to patients imaged with Ga-68-PSMA-11. Conclusion: F-18-DCFPyL and Ga-68-PSMA-11 had comparable biodistribution and lesion uptake. Patients imaged with F-18-DCFPyL demonstrated clinical benefit to PSMA RLT comparable to those imaged with Ga-68-PSMA-11, and either agent can be used for screening patients.