Toward a Structured Imaging Reporting System for Kidney Masses: The Molecular Imaging Perspective on KI-RADS

Area of Science:

• Oncology
• Radiology
• Molecular Imaging

Background:

• The Kidney Imaging Reporting and Data System (KI-RADS) requires imaging characteristics linked to tumor biology for optimal risk stratification of indeterminate renal masses.
• Multi-parametric magnetic resonance imaging is valuable for staging and characterization, but molecular imaging offers more fundamental biological insights.

Purpose of the Study:

• To review current renal mass characterization imaging approaches.
• To discuss the evidence and potential of molecular imaging in renal mass risk stratification.
• To propose a molecular imaging-focused companion KI-RADS framework.

Main Methods:

• Review of current imaging modalities for renal mass characterization.
• Discussion of radiotracers like 99mTc-sestamibi and 89Zr-girentuximab.
• Exploration of synergy between anatomic imaging, molecular imaging, and biopsy.

Main Results:

• Molecular imaging agents (99mTc-sestamibi, 89Zr-girentuximab) show promise for risk stratification.
• Studies demonstrate strong correlations between molecular imaging findings and tumor biology.
• A proposed molecular imaging-based KI-RADS framework uses a five-point Likert scale.

Conclusions:

• Molecular imaging provides crucial biological insights for indeterminate renal masses.
• Integration of molecular imaging into KI-RADS is warranted for improved risk stratification.
• Future directions include data integration and artificial intelligence applications.