18F-Fluciclovine PET/CT Impact on Predicting Clinical Outcome of 177Lu-PSMA-617 Therapy in Patients With Prostate Cancer

This a single-center, prospective, exploratory study. Patients with metastatic castration-resistant prostate cancer (mCRPC) scheduled to undergo Lutetium labelled prostate-specific membrane antigen radioligand therapy (LuPSMA RLT) at the West Los Angeles VA (WLA-VA) will be imaged with a baseline F-18 fluorodeoxyglucose positron emission tomography/computed tomography 18F-FDG PET/CT and a 18F-DCFPyL PET/CT (18F-DCFPyL (2-(3-{1-carboxy-5-\[(6-18F-fluoro-pyridine-3-carbonyl)-amino\]-pentyl}-ureido)-pentanedioic acid)positron emission tomography/computed tomography , as per standard of care in our institution. All patients further undergo eventual follow-up prostate-specific membrane antigen positron emission tomography (PSMA PET) after the 2nd, 4th, and 6th LuPSMA RLT cycle. In this prospective study, an18F-Fluciclovine positron emission tomography/computed tomography ( Axumin PET/CT )will be additionally obtained at baseline (pre-LuPSMA RLT), and after the 2nd, 4th, 6th LuPSMA RLT cycles. Axumin PET/CT will be acquired within 7 days from the PSMA PET. This study is open to Veterans only.

The imaging analysis will consist in obtaining quantitative measurements of lesion uptake on the pre- and post-LuPSMA RLT (lesion and whole-body SUVmax, SUVmean and tumor volume) at each time point on all PET/CT scans. PET metrics at the lesion- and whole-body level will be compared among different PET radiopharmaceuticals at the same time point, and changes over time will be assessed. All patients will be followed-up at our institution and clinical outcome will be correlated to the imaging analysis assessment.