RM2 was shown to be a potent GRPr antagonist. Pharmacokinetics and imaging studies indicate that (111)In-RM2 and (68)Ga-RM2 are ideal candidates for clinical SPECT and PET studies.

Purpose: A novel [68 Ga]-labeled DOTA-4-amino-1-carboxymethyl-piperidine-D-Phe-Gln-Trp-Ala-ValGly-His-Sta-Leu-NH 2 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 assessment of PET/CT images included evaluation of intraprostatic (12 subsextants) and pelvic nodal uptake 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 eitherWe 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