BAY 1075553 PET-CT for Staging and Restaging Prostate Cancer Patients: Comparison with [ 18 F] Fluorocholine PET-CT (Phase I Study (original) (raw)

Purpose: (2RS,4S)-2-[ 18 F]Fluoro-4-phosphonomethyl-pentanedioic acid (BAY1075553) shows increased uptake in prostate cancer cells. We compared the diagnostic potential of positron emission tomography (PET)-X-ray computed tomography (CT) imaging using BAY1075553 versus [ 18 F]f luorocholine (FCH) PET-CT. Procedures: Twelve prostate cancer patients (nine staging, three re-staging) were included. The mean prostate-specific antigen in the primary staging and re-staging groups was 21.5±12 and 73.6±33 ng/ml, respectively. Gleason score ranged from 5–9. In nine patients imaged for pre-operative staging, the median Gleason score was 8 (range, 7–9). PET acquisition started with dynamic PET images in the pelvic region followed by static whole-body acquisition. The patients were monitored for 5–8 days afterward for adverse events. Results: There were no relevant changes in laboratory values or physical examination. Urinary bladder wall received the largest dose equivalent 0.12 mSv/MBq. The whole-body mean effective dose was 0.015 mSv/MBq. There was a significant correlation between detected prostatic lesions by the two imaging modalities (Kappa=0.356, PG0.001) and no significant difference in sensitivity (P=0.16) and specificity (P=0.41). The sensitivity and specificity of PET imaging using BAY1075553 for lymph node (LN) staging was 42.9 % and 100 %, while it was 81.2 % and 50 % using FCH. The two modalities were closely correlated regarding detection of LNs and bone metastases, although BAY1075553 failed to detect a bone marrow metastasis. Degenerative bone lesions often displayed intense uptake of BAY1075553. Conclusions: BAY1075553 PET-CT produced no adverse effects, was well tolerated, and detected primary and metastatic prostate cancer. FCH PET-CT results were superior, however, with respect to detecting LN and bone marrow metastases.