Clinical Scorecard: Association of Glucose Metabolism in Brain and Liver with Disease Progression in Multiple Myeloma

At a Glance

Key Highlights

• 18F-FDG PET/CT is essential for staging, assessing disease burden, extramedullary disease, and metabolic response in multiple myeloma.
• Brain-to-liver ratio (B2LR) of glucose uptake on PET/CT may differentiate active disease from remission in multiple myeloma.
• Complete metabolic response on PET/CT after CAR-T therapy correlates with prolonged progression-free survival.

Guideline-Based Recommendations

Diagnosis

• Use 18F-FDG PET/CT to evaluate disease burden and detect extramedullary disease in multiple myeloma.
• Assess standardized uptake value (SUV) and Deauville score (1-5) to characterize metabolic activity.
• Calculate brain-to-liver ratio (B2LR) from PET/CT images to aid in disease activity assessment.

Management

• Incorporate PET/CT findings, including metabolic response, into treatment planning and monitoring.
• Consider complete metabolic response on PET/CT as a favorable prognostic indicator post-CAR-T therapy.

Monitoring & Follow-up

• Perform serial 18F-FDG PET/CT imaging for monitoring treatment response and disease progression.
• Evaluate changes in SUV and B2LR to assess metabolic response over time.

Risks

• Interpret SUV >2.5 cautiously as it is not specific for neoplasia.
• Ensure patients are off plasma cell-directed therapy for at least 2 weeks before PET/CT to avoid confounding uptake.

Patient & Prescribing Data

Multiple myeloma patients undergoing CAR-T therapy with pre-treatment PET/CT imaging

Complete metabolic response on PET/CT correlates with improved progression-free survival; B2LR may serve as a biomarker for disease activity and prognosis.

Clinical Best Practices

• Standardize PET/CT imaging protocols for reproducibility and accurate quantification of glucose uptake.
• Define multiple regions of interest (ROIs) in cerebral cortex and liver to calculate reliable B2LR.
• Use IMWG criteria for cytogenetic risk and response assessment in conjunction with imaging findings.
• Obtain histologic confirmation of extramedullary disease when identified on imaging due to its prognostic significance.
• Ensure ethical approval and informed consent for use of patient imaging and data in research.

References

• IMWG criteria for multiple myeloma response and risk assessment
• 18F-FDG PET/CT in multiple myeloma: clinical utility and prognostic implications
• Warburg effect and tumor glucose metabolism