In Vivo Imaging of Prostate Cancer Using ( 68 Ga)-Labeled

Purpose: A novel ( 68 Ga)-labeled DOTA-4-amino-1-carboxymethyl-piperidine-D-Phe-Gln-Trp-Ala-Val- Gly-His-Sta-Leu-NH2 peptide (BAY86-7548) having high affinity to bombesin receptor subtype II to detect primary and metastatic prostate carcinoma using positron emission tomography/computed tomography (PET/CT) was synthesized and evaluated for prostate cancer. Experimental Design: In this first human study with BAY86-7548, 14 men scheduled for radical prostatectomy (n ¼ 11) or with biochemical recurrence after surgery or hormonal therapy (n ¼ 3) were enrolled. The patients received an intravenous injection of BAY86-7548 followed by over 60-minute dynamic imaging of prostate gland (n ¼ 10) and/or subsequent whole-body imaging (n ¼ 14). The visual assessmentofPET/CTimagesincludedevaluationofintraprostatic(12subsextants)andpelvicnodaluptake of BAY86-7548 in 11 surgical patients and detection of potential metastatic foci in all patients. In patients with biochemical recurrence, results were compared with those of either ( 11 C)-acetate (n ¼ 2) or ( 18 F)- fluoromethylcholine (n ¼ 1) PET/CT. Results: We found a sensitivity, specificity, and accuracy of 88%, 81% and 83%, respectively, for detection of primary PCa and sensitivity of 70% for metastatic lymph nodes using histology as gold standard. BAY86-7548 correctly detected local recurrence in prostate bed and showed nodal relapse in accordance with ( 11 C)-acetate PET/CT in 2 patients with biochemical relapse. In the third hormone refractory patient, BAY86-7548 failed to show multiple bone metastases evident on ( 18 F)-fluoromethyl- choline PET/CT. Conclusion: BAY86-7548 PET/CT is a promising molecular imaging technique for detecting intrapro- static prostate cancer. Clin Cancer Res; 19(19); 5434-43. � 2013 AACR.