MRI differentiation of low-grade from high-grade appendicular chondrosarcoma
- 807 Downloads
To identify magnetic resonance imaging (MRI) features which differentiate low-grade chondral lesions (atypical cartilaginous tumours/grade 1 chondrosarcoma) from high-grade chondrosarcomas (grade 2, grade 3 and dedifferentiated chondrosarcoma) of the major long bones.
We identified all patients treated for central atypical cartilaginous tumours and central chondrosarcoma of major long bones (humerus, femur, tibia) over a 13-year period. The MRI studies were assessed for the following features: bone marrow oedema, soft tissue oedema, bone expansion, cortical thickening, cortical destruction, active periostitis, soft tissue mass and tumour length. The MRI-features were compared with the histopathological tumour grading using univariate, multivariate logistic regression and receiver operating characteristic curve (ROC) analyses.
One hundred and seventy-nine tumours were included in this retrospective study. There were 28 atypical cartilaginous tumours, 79 grade 1 chondrosarcomas, 36 grade 2 chondrosarcomas, 13 grade 3 chondrosarcomas and 23 dedifferentiated chondrosarcomas. Multivariate analysis demonstrated that bone expansion (P = 0.001), active periostitis (P = 0.001), soft tissue mass (P < 0.001) and tumour length (P < 0.001) were statistically significant differentiating factors between low-grade and high-grade chondral lesions with an area under the ROC curve of 0.956.
On MRI, bone expansion, active periostitis, soft tissue mass and tumour length can reliably differentiate high-grade chondrosarcomas from low-grade chondral lesions of the major long bones.
• Accurate differentiation of low-grade from high-grade chondrosarcomas is essential before surgery
• MRI can reliably differentiate high-grade from low-grade chondrosarcomas of long bone
• Differentiating features are bone expansion, periostitis, soft tissue mass and tumour length
• Presence of these four MRI features demonstrated a diagnostic accuracy (AUC) of 95.6 %
• The findings may result in more accurate diagnosis before definitive surgery
KeywordsLow-grade chondrosarcoma High-grade chondrosarcoma Long bone MRI Differentiation
The images of the patients in Figs. 1 and 3 have been previously published by us in the following article: The imaging of cartilaginous bone tumours. II. Chondrosarcoma. Douis H, Saifuddin A. Skeletal Radiol. 2013 May;42(5):611-26
We have to emphasize however that the images are not exactly the same and that we either used a different slice position or a different MRI-sequence. Therefore, these exact images have not been previously published. We have nevertheless obtained permission from the publisher Springer to reprint the images.
- 1.Hogendoorn PCW, Bovee JM, Nielsen GP (2013) Chondrosarcoma (grades I-III), including primary and secondary variants and periosteal chondrosarcoma. In: Fletcher CDM, Bridge JA, Hogendoorn PCW, Mertens F (eds) World Health Organization Classification of Tumours of Soft Tissue and Bone. IARC Press, Lyon, pp 264–268Google Scholar
- 2.Inwards CHP (2013) In: Fletcher CDM, Bridge JA, Hogendoorn PCW, Mertens F (eds) World Health Organization Classification of Tumours of Soft Tissue and Bone. IARC Press, Lyon, pp 269–270Google Scholar