Novel radiopharmaceuticals for bladder cancer evaluation

Area of Science:

• Nuclear Medicine
• Oncology
• Radiopharmaceutical Development

Background:

• Molecular imaging of bladder cancer (BC) faces challenges with [¹⁸F]FDG PET/CT due to limitations in assessing primary tumors and differentiating malignant from physiological urinary activity.
• Development of novel PET radiopharmaceuticals is crucial for enhancing diagnostic accuracy and optimizing patient management in BC.
• Emerging radiopharmaceuticals present potential advantages for BC evaluation.

Purpose of the Study:

• To conduct a narrative review summarizing the available evidence on alternative PET radiopharmaceuticals for bladder cancer evaluation.
• To assess the role of novel agents in improving the diagnosis, staging, and therapy monitoring of BC.

Main Methods:

• A narrative review of 14 studies involving 158 patients across six countries.
• Investigated radiopharmaceuticals included [¹⁸F]/[⁶⁸Ga]-FAPI, [¹⁸F]Fluciclovine, [⁶⁸Ga]Ga-N188, and ⁶⁴CuCl2.
• [¹⁸F]FDG PET/CT was used as a comparator in four studies.

Main Results:

• FAPI agents demonstrated the highest lesion detectability and superior image contrast.
• [¹⁸F]Fluciclovine showed high specificity for muscle-invasive bladder cancer staging with favorable biodistribution.
• PSMA-targeted imaging, ⁶⁴CuCl2, and [⁶⁸Ga]Ga-N188 highlighted a shift towards personalized and theranostic molecular imaging.

Conclusions:

• While [¹⁸F]FDG PET/CT remains a reference, novel PET agents show encouraging results for improving BC staging and therapy monitoring.
• Broader clinical implementation of these novel agents necessitates multicentric validation and standardized imaging protocols.
• The findings underscore the potential of personalized molecular imaging in bladder cancer management.