WHO Bone and Soft Tissue Tumor Classification (5th Edition)
- What Radiologists Should Know*
Presented by: [Your Name]
Date: [Date]
Overview
- Updated Tumor Classifications and Nomenclature
- Molecular and Genetic Insights
- Imaging Features of Key Tumors
- Implications for Differential Diagnosis
- Practical Considerations for Radiologists
Updated Tumor Classifications
New Entities & Subtypes
- Bone Tumors:
- CIC-rearranged sarcoma
- NTRK-rearranged spindle cell neoplasms
- Soft Tissue Tumors:
- EWSR1::SMAD3-rearranged fibroblastic tumor
- Myxoid pleomorphic liposarcoma
- Nomenclature Changes:
- Malignant Fibrous Histiocytoma (MFH) → Undifferentiated Pleomorphic Sarcoma (UPS)
Grading & Classification Changes
Refinements in Tumor Grading
- Chondrosarcoma: Enhanced focus on imaging + histology for grading
- Giant Cell Tumor of Bone: Incorporation of H3F3A mutations
Molecular and Genetic Insights
Molecular Markers to Know
- Synovial Sarcoma: SS18-SSX fusion
- Ewing Sarcoma: EWSR1-FLI1 translocation
- Dedifferentiated Liposarcomas: MDM2 amplification
Radiogenomics in Practice
Linking Imaging to Molecular Data
- Fat-containing masses with solid nodules suggest MDM2-amplified liposarcomas
- Aggressive soft tissue masses with calcification may hint at Ewing sarcoma
Imaging Features of Key Bone Tumors
Bone Tumors: What to Look For
- Osteosarcoma: Variants like conventional, telangiectatic, small cell
- Chondrosarcoma: MRI differentiates from enchondroma (focus on cortical breach & soft tissue extension)
Imaging Features of Soft Tissue Tumors
Soft Tissue Tumors: Radiologic Highlights
- Liposarcoma Subtypes:
- Well-differentiated: Fatty with thick septa
- Dedifferentiated: Non-lipomatous components
- Rhabdomyosarcoma:
- Embryonal: Intermediate aggression
- Alveolar: More aggressive, often with necrosis
Implications for Differential Diagnosis
Benign vs Malignant Mimics
- Fibrous Dysplasia vs Low-grade Osteosarcoma
- Nodular Fasciitis mimicking Sarcoma (benign but aggressive appearance)
Undifferentiated/Unclassified Tumors
Handling Unclassified Tumors
- Rely on biopsy & molecular testing
- Imaging helps guide tissue sampling to viable areas
Practical Considerations for Radiologists
Biopsy & Treatment Planning
- Biopsy Guidance: Target most viable, non-necrotic areas
- Avoid Contamination: Plan approach to prevent spreading tumor cells
Staging & Follow-Up
Staging and Post-Treatment Imaging
- PET-CT: Metabolic activity for staging and treatment response
- MRI: Preferred for local recurrence detection
Multidisciplinary Collaboration
Team Approach to Diagnosis & Management
- Work closely with pathologists & oncologists
- Correlate imaging with molecular findings for accurate diagnosis
Conclusion
Key Takeaways
- WHO updates emphasize molecular insights alongside imaging
- Radiologists play a critical role in early detection, diagnosis, and follow-up
- Stay updated on classifications for accurate reporting and management guidance
Questions & Discussion
- Thank You!*
- Questions?*
- Let’s discuss any specific cases or tumor types of interest.*
