Prospective Evaluation of 68Ga-RM2 PET/MRI in Patients with Biochemical Recurrence of Prostate Cancer and Negative Findings on Conventional Imaging

• DOI: 10.2967/jnumed.117.197624
• Publication Date: 2017-10-30T11:55:15Z
• Authors: Ryogo Minamimoto; Ida Sonni; Steven Hancock; Shreyas Vasanawala; Andreas Loening; Sanjiv S. Gambhir; Andrei Iagaru
• Keywords: Biochemical recurrence

⁶⁸Ga-labeled DOTA-4-amino-1-carboxymethyl-piperidine-d-Phe-Gln-Trp-Ala-Val-Gly-His-Sta-Leu-NH₂ (⁶⁸Ga-RM2) is a synthetic bombesin receptor antagonist that targets gastrin-releasing peptide (GRPr). GRPr proteins are highly overexpressed in several human tumors, including prostate cancer (PCa). We present data from the use of ⁶⁸Ga-RM2 patients with biochemical recurrence (BCR) PCa and negative findings on conventional imaging. <b>Methods:</b> enrolled 32 men BCR PCa, who were 59–83 y old (mean ± SD, 68.7 6.4 y). Imaging started at 40–69 min (mean, 50.5 6.8 min) after injection 133.2–151.7 MBq 140.6 7.4 MBq) using time-of-flight–enabled simultaneous PET/MRI scanner. T1-weighted, T2-weighted, diffusion-weighted images acquired. <b>Results:</b> All had rising level prostate-specific antigen (PSA) (range, 0.3–119.0 ng/mL; mean, 10.1 21.3 ng/mL) imaging (CT or MRI, ^99mTc-methylene diphosphonate bone scan) before enrollment. The observed PET detection rate was 71.8%. identified recurrent 23 participants, whereas MRI scan compatible 11 patients. PSA velocity 0.32 0.59 ng/mL/y 0.04–1.9 ng/mL/y) 2.51 2.16 0.13–8.68 positive (<i>P</i> = 0.006). <b>Conclusion:</b>⁶⁸Ga-RM2 can be used for assessment expression PCa. High uptake multiple areas lesions suggests promising radiopharmaceutical localization disease