68Ga-RM2 PET/MRI may enhance detection of prostate cancer recurrence

Study findings presented at the 2023 Radiological Society of North America (RSNA) conference showed that targeting gastrin releasing peptide receptors (GRPRs) with 68Ga-RM2 PET/MRI may significantly enhance the diagnosis of prostate cancer recurrence.¹

“The collective findings of this comparative imaging trial and other published studies provide compelling evidence that 68Ga-RM2 PET/MRI not only outperforms conventional imaging with MRI but also shows higher reliability and number of lesions detected, which could potentially affect subsequent patient management,” wrote Dr. Duan, a postdoctoral research fellow at the Stanford University School of Medicine

The prospective phase 2/3 study compared 68Ga-RM2 positron emission tomography (PET)/magnetic resonance imaging (MRI) vs. MRI alone in 100 men with a post-prostatectomy prostate specific antigen (PSA) level > 0.2 ng/mL or a PSA level > above nadir after radiotherapy.

(Editor’s note: This article has been adapted from its original publication in our sister site Diagnostic Imaging.)

Findings from the research revealed that 68Ga-RM2 PET/MRI had an 85.2% sensitivity rate for diagnosing biochemical recurrence of prostate cancer in comparison to a 49.4% sensitivity rate for MRI alone.

While both modalities offered comparable specificity at 100%, use of 68Ga-RM2 PET/MRI led to a significantly higher detection of prostate cancer lesions (143 vs. 96 for MRI alone), according to the research, which was awarded with the RSNA 2023 Trainee Research Prize in the Nuclear Medicine and Molecular Imaging category

Noting that GRPRs are overexpressed in prostate cancer, study author Heying Duan, M.D., M.B.A, said 68Ga-RM2 PET/MRI may prove to be a viable option for diagnosing and facilitating timely intervention for biochemical recurrence of prostate cancer.

“The collective findings of this comparative imaging trial and other published studies provide compelling evidence that 68Ga-RM2 PET/MRI not only outperforms conventional imaging with MRI but also shows higher reliability and number of lesions detected, which could potentially affect subsequent patient management,” wrote Dr. Duan, a postdoctoral research fellow at the Stanford University School of Medicine.

Reference

1. Duan H, Moradi F, Davidzon GA, et al. Final analysis of a prospective, single-center, phase II/III imaging trial of 68Ga-RM2 PET/MRI in patients with biochemical recurrence of prostate cancer. Presented at the RSNA 2023 109th Scientific Assembly and Annual Meeting Nov. 26-30, 2023. Available at https://www.rsna.org/annual-meeting . Accessed December 13, 2023.