JoVE - Journal of Visualized Experiments
JoVE Visualize
Contact Us

Additive Value of [68Ga]Ga-RM26 PET/CT to [68Ga]Ga-PSMA-617 PET/CT in Detecting Pelvic Lymph Node Metastasis in Prostate Cancer: A Prospective, Single-Center, Phase II Study

  • 0Department of Urology, Disorders of Prostate Cancer Multidisciplinary Team, National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China.
Journal of Nuclear Medicine : Official Publication, Society of Nuclear Medicine +

|

March 20, 2025

|

March 20, 2025

View abstract on PubMed

Summary

This summary is machine-generated.

Combining [<sup>68</sup>Ga]Ga-RM26 PET/CT and [<sup>68</sup>Ga]Ga-PSMA-617 PET/CT improves detection of prostate cancer lymph node metastasis. Dual-target imaging identified additional pelvic lymph node metastases missed by single-tracer scans, enhancing diagnostic accuracy.

Area Of Science

  • Nuclear Medicine
  • Oncology
  • Radiopharmaceuticals

Background

  • Accurate lymph node staging is critical for prostate cancer treatment and prognosis.
  • [<sup>68</sup>Ga]Ga-PSMA-617 PET/CT has limitations in detecting pelvic lymph node metastasis (PLNM).
  • [<sup>68</sup>Ga]Ga-RM26 PET/CT targets the gastrin-releasing peptide receptor and may complement [<sup>68</sup>Ga]Ga-PSMA-617 PET/CT.

Purpose Of The Study

  • To evaluate the diagnostic performance of [<sup>68</sup>Ga]Ga-RM26 PET/CT and [<sup>68</sup>Ga]Ga-PSMA-617 PET/CT in detecting PLNM.
  • To assess the role of [<sup>68</sup>Ga]Ga-RM26 PET/CT in complementing [<sup>68</sup>Ga]Ga-PSMA-617 PET/CT for PLNM detection.

Main Methods

  • Prospective study of 68 newly diagnosed, untreated prostate cancer patients.
  • Patients underwent both [<sup>68</sup>Ga]Ga-RM26 PET/CT and [<sup>68</sup>Ga]Ga-PSMA-617 PET/CT.
  • Followed by radical prostatectomy and extended pelvic lymph node dissection for pathological confirmation.

Main Results

  • [<sup>68</sup>Ga]Ga-RM26 PET/CT detected additional PLNMs in 50% of patients missed by [<sup>68</sup>Ga]Ga-PSMA-617 PET/CT (patient-based).
  • Combined dual-target imaging achieved a sensitivity of 0.76 and specificity of 0.85 (patient-based).
  • [<sup>68</sup>Ga]Ga-RM26 PET/CT identified 41.4% of positive nodes missed by [<sup>68</sup>Ga]Ga-PSMA-617 PET/CT (lesion-based); combined sensitivity 0.71, specificity 0.99.

Conclusions

  • Dual-target imaging with [<sup>68</sup>Ga]Ga-RM26 PET/CT identifies additional pelvic lymph node metastases.
  • Combining [<sup>68</sup>Ga]Ga-RM26 PET/CT and [<sup>68</sup>Ga]Ga-PSMA-617 PET/CT significantly increases diagnostic sensitivity for PLNM.
  • This combined approach offers improved detection with minimal compromise in specificity for prostate cancer staging.

Keywords:

Related Concept Videos

Conjugate Addition (1,4-Addition) vs Direct Addition (1,2-Addition) 01:27

3.1K

α,β-Unsaturated carbonyl compounds with two electrophilic sites, the carbonyl carbon, and the β carbon, are susceptible to nucleophilic attack via two modes: conjugate or 1,4-addition and direct or 1,2-addition.
Conjugate addition results in a thermodynamically stable product. The reaction retains the stronger C=O bond at the expense of the weaker C=C π bond. The process is slow as the β carbon is less electrophilic than the carbonyl carbon.
Direct addition products are...

EDTA: Auxiliary Complexing Reagents 01:26

521

EDTA titrations are usually carried out in highly basic conditions, where the fully deprotonated form of EDTA, Y4−, actively complexes with the free metal ions in the solution. Several metal ions precipitate as hydrous oxide (hydroxides, oxides, or oxyhydroxides) under these conditions, lowering the concentration of free metal ions in the solution. For this reason, auxiliary complexing agents or ligands such as ammonia, tartrate, citrate, or triethanolamine are used in EDTA titrations to...

Cycloaddition Reactions: Overview 01:16

2.5K

Cycloadditions are one of the most valuable and effective synthesis routes to form cyclic compounds. These are concerted pericyclic reactions between two unsaturated compounds resulting in a cyclic product with two new σ bonds formed at the expense of π bonds. The [4 + 2] cycloaddition, known as the Diels–Alder reaction, is the most common. The other example is a [2 + 2] cycloaddition.

The feasibility of cycloaddition reactions under thermal and photochemical conditions can be...

[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction 01:16

9.9K

The Diels–Alder reaction is an example of a thermal pericyclic reaction between a conjugated diene and an alkene or alkyne, commonly referred to as a dienophile. The reaction involves a concerted movement of six π electrons, four from the diene and two from the dienophile, forming an unsaturated six-membered ring. As a result, these reactions are classified as [4+2] cycloadditions.

From a molecular orbital perspective, the interacting lobes of the two π systems must be in phase...

Conjugate Addition to α,β-Unsaturated Carbonyl Compounds 01:09

4.0K

α,β-Unsaturated carbonyl compounds are molecules bearing a carbonyl and alkene functionality in conjugation with each other. The conjugation in the molecule leads to three resonance structures. The hybrid form exhibits two probable electrophilic sites: the carbonyl carbon and the β carbon.

A simple nucleophilic attack at the carbonyl center results in an alkoxy intermediate, which gives the direct or 1,2-addition product upon further protonation.

When the nucleophile attacks the β...

Additives and Fillers in Concrete 01:29

77

Additives and fillers are integral to enhancing the properties of concrete. Pozzolans and blast-furnace slag are additives or admixtures due to their reactions with calcium hydroxide released during cement hydration. Fillers, which are finely ground and similar in fineness to Portland cement, improve concrete attributes such as workability density, and reduce capillary bleeding or cracking. Some fillers possess hydraulic properties or participate in benign reactions within the cement paste.
The...