Chondrosarcoma¶

Definition¶

Chondrosarcoma is a malignant cartilage-forming tumor that rarely affects the spine (approximately 7–12% of all chondrosarcomas). It typically involves the vertebral body or posterior elements and is characterized by chondroid (cartilage) matrix mineralization. It is usually low to intermediate grade and slow-growing.

Imaging Findings¶

CT¶

Lytic, destructive mass with chondroid matrix — characteristic "rings and arcs" or "popcorn" pattern of calcification
Cortical destruction and soft tissue extension
Endosteal scalloping
The chondroid matrix pattern is the key diagnostic feature

MRI¶

Very high T2 signal — Characteristic of cartilage tumors (lobulated, bright T2 signal resembling hyaline cartilage)
Low to intermediate T1 signal
Peripheral and septal "rings and arcs" enhancement pattern (enhancing septa around non-enhancing cartilage lobules)
Epidural extension may cause cord compression

Clinical Pearl

The combination of a destructive spinal mass with "rings and arcs" chondroid calcification on CT and very high lobulated T2 signal on MRI is virtually diagnostic of a cartilage tumor (enchondroma or chondrosarcoma). In the spine, chondrosarcoma is far more common than enchondroma.

Management¶

En bloc surgical resection with wide margins is the treatment of choice
Chondrosarcomas are resistant to conventional chemotherapy and radiation
Proton beam therapy may be used for unresectable or residual disease
Recurrence is common with inadequate margins

Key Points¶

Chondrosarcoma produces chondroid matrix ("rings and arcs" calcification on CT)
Very high T2 signal on MRI reflects cartilage content
The spine is an uncommon but recognized location
Resistant to chemotherapy and radiation — surgery is the primary treatment
Distinguish from chordoma (midline, no chondroid matrix) and osteosarcoma (osteoid matrix)

References¶

Katonis P, Alpantaki K, Michail K, Lianoudakis S, Christoforakis Z, Tzanakakis G, Karantanas A. Spinal chondrosarcoma: a review. Sarcoma. 2011;2011:378957. doi:10.1155/2011/378957. Available from: https://pubmed.ncbi.nlm.nih.gov/21437176/
Lloret I, Server A, Bjerkehagen B. Primary spinal chondrosarcoma: radiologic findings with pathologic correlation. Acta Radiol. 2006;47(1):77-84. Available from: https://pubmed.ncbi.nlm.nih.gov/16498937/
Douis H, Saifuddin A. The imaging of cartilaginous bone tumours. II. Chondrosarcoma. Skeletal Radiol. 2013;42(5):611-626. doi:10.1007/s00256-012-1521-3. Available from: https://pubmed.ncbi.nlm.nih.gov/23053201/
Ollivier L, Vanel D, Leclère J. Imaging of chondrosarcomas. Cancer Imaging. 2003;4(1):36-38. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC1434527/
Nisson PL, Berger GK, James WS, Hurlbert RJ. Surgical Techniques and Associated Outcomes of Primary Chondrosarcoma of the Spine. World Neurosurg. 2018;119:e32-e45. doi:10.1016/j.wneu.2018.06.189. Available from: https://pubmed.ncbi.nlm.nih.gov/30026140/
Chondrosarcoma. Radiopaedia.org. Available from: https://radiopaedia.org/articles/chondrosarcoma