Learning objectives
-To present the characteristic radiographic appearance of the most common benign and malignant chondroid tumors.
-To stress the semiology and symptoms that should raise concern for malignancy.
Background
Chondroid lesions like enchondromas and osteochondromas are some of the most frequent bone lesions.
Simple radiographs are usually enough for their diagnosis.
Differencing benign chondroid tumors from low grade chondrosarcomas can be sometimes challenging due to subtle differences in their semiology.
Imaging findings OR Procedure Details
Chondroid matrix lytic bone lesions (chondroid matrix usually identified as rings and arcs or popcorn calcifications),
most of them benign,
can show some symptoms and radiologic findings that make us think of possible malignancy.
General features of enchondromas and osteochondromas,
findings raising concern for malignancy and chondrosarcoma features will be discussed
Enchondroma:
Centrally located,
they can grow until skeletal maturity.
Chondral calcifications will usually be seen,
except in short tubular bones (phalanges) where they can be pure lytic lesions.
Common benign findings in enchondromas:
-Subtle...
Conclusion
All radiologists should be aware of normal and abnormal findings in chondroid benign lesions,
as well as the aggressiveness signs associated to malignant chondroid lesions.
CT is a valuable tool for measuring endosteal scalloping and assessing soft tissue masses or cartilage cap thickness,
wich are some of the main differences between benign and malignant lesions.
Confident assessment of the worrisome signs of low grade chondrosarcomas is crucial for the diagnostic and therapeutic management of patients.
References
1) Murphey M et al.
From the Archives of the AFIP.
Imaging of Primary Chondrosarcoma: Radiologic-Pathologic Correlation.
RadioGraphics 2003; 23:1245–1278.
2) Murphey M et al.
From the Archives of the AFIP.
Imaging of Osteochondroma: Variants and Complications with Radiologic-Pathologic Correlation.
RadioGraphics 2000; 20:1407–1434
3) Littrell et al.
Radiographic,
CT and MR Imaging Features of Dedifferentiated Chondrosarcomas: A Retrospective Review of 174 De Novo Cases.
RadioGraphics 2004; 24:1397–1409
4) Bernard S et al.
Improved Diferrentiation of Benign Osteochondromas from Secondary Chondrosarcomas with Standardized Measurement of Cartilage...