Integration of Cytomorphological Analysis and 18F-FDG PET/CT Imaging for Non-Invasive Assessment of the Bone Marrow Immune Microenvironment in Multiple Myeloma

Overview

This study introduces ImmunoCast-MM, a deep learning framework that integrates cytomorphological analysis and 18F-FDG PET/CT imaging to assess the bone marrow immune microenvironment in multiple myeloma. The framework demonstrated significant correlations with flow cytometric measurements.

Background

The bone marrow immune microenvironment (BMME) plays a crucial role in the progression and treatment response of multiple myeloma (MM). Traditional diagnostic methods focus primarily on tumor burden, often neglecting the immune status.

Data Highlights

Key Findings

• ImmunoCast-MM effectively correlates cytomorphological indices with flow cytometric fractions (Spearman ρ values of 0.68–0.81).
• Unsupervised clustering identified immune-competent and immune-exhausted archetypes with differing progression-free survival and daratumumab response.
• Incorporating the Immune Dysfunction Index (IDI) improved the concordance index from 0.58 to 0.75.
• The area under the receiver operating characteristic curve for daratumumab response increased from 0.55 to 0.81 when including the IDI.

Clinical Implications

The integration of cytomorphological analysis and PET/CT imaging offers a non-invasive approach to evaluate the bone marrow immune microenvironment in multiple myeloma.

Conclusion

ImmunoCast-MM represents a significant advancement in the non-invasive assessment of the BMME in multiple myeloma.

Related Resources & Content

1. Blood Cancer Journal, 2021 -- Development of a new risk stratification system for patients with newly diagnosed multiple myeloma using R-ISS and 18F-FDG PET/CT
2. Blood Cancer Journal, 2025 -- Association of Glucose Metabolism in Brain and Liver with Disease Progression in Multiple Myeloma
3. European Radiology, 2024 -- Loss of T2 Signal Intensity in the Spleen on MRI Correlates with Disease Severity in Multiple Myeloma
4. Blood Cancer Journal, 2024 -- Elevated Levels of Circulating Cell-Free Tumor DNA at Diagnosis Are Associated with Disease Progression and Identify Multiple Myeloma Patients at High Risk for Poor Outcomes
5. Multiple Myeloma, Version 5.2026, NCCN Clinical Practice Guidelines In Oncology - PubMed
6. Li et al. Cancer Imaging, 2025 -- Meta-analysis on PET/CT features in multiple myeloma
7. Immunophenotypic changes in the tumor and tumor microenvironment during progression to multiple myeloma | PLOS Genetics
8. Multiple Myeloma, Version 5.2026, NCCN Clinical Practice Guidelines In Oncology - PubMed
9. Li et al. Cancer Imaging (2025) 25:94
10. Immunophenotypic changes in the tumor and tumor microenvironment during progression to multiple myeloma | PLOS Genetics