Head-to-Head Comparison of ⁶⁸Ga-NOTA (⁶⁸Ga-NGUL) and ⁶⁸Ga-PSMA-11 in Patients with Metastatic Prostate Cancer: A Prospective Study.

Abstract

⁶⁸Ga-NOTA Glu-Urea-Lys (NGUL) is a novel prostate-specific membrane antigen (PSMA)-targeting tracer used for PET/CT imaging. This study aimed to compare performance in the detection of primary and metastatic lesions and to compare biodistribution between ⁶⁸Ga-NGUL and ⁶⁸Ga-PSMA-11 in the same patients with prostate cancer. <b>Methods:</b> Eleven patients with metastatic prostate cancer were prospectively recruited. The quantitative tracer uptake was determined in normal organs and in primary and metastatic lesions. <b>Results:</b>⁶⁸Ga-NGUL showed significantly lower normal-organ uptake and rapid urinary clearance. The number and sites of detected PSMA-positive primary and metastatic lesions were identical, and no significant quantitative uptake difference was observed. ⁶⁸Ga-NGUL showed a relatively lower tumor-to-background ratio than ⁶⁸Ga-PSMA-11. <b>Conclusion:</b> In a head-to-head comparison with ⁶⁸Ga-PSMA-11, ⁶⁸Ga-NGUL showed lower uptake in normal organs and similar performance in detecting PSMA-avid primary and metastatic lesions. ⁶⁸Ga-NGUL could be a valuable option for PSMA imaging.