Spinal Metastasis

spinal metastasis

This patient presented with severe neck pain after a fall. He had known transitional cell carcinoma metastases to bone. The above axial CT shows a metastasis eroding much of the right side of the axis. There is a large associated soft tissue mass which extends into the spinal canal. There is also a fracture of the left lamina of C2, which appears acute.

Lytic bone metastases to the spine often involve the body-pedicle junction, but may be anywhere. Destruction of posterior cortex or pedicle is a useful clue suggesting metastasis. Lumbar vertebrae are involved more frequently than thoracic or cervical. Lytic metastases may arise from breast, lung, kidney, thyroid, pharyngeal, gastrointestinal, urothelial or gynaecological malignancy, or may be due to melanoma, chordoma or paraganglioma. Transitional cell carcinoma may give rise to lytic or sclerotic metastases.

In some cases there may be difficulty differentiating metastases from benign osteoporotic compression fracture. Up to 25% of fractures in apparently osteopenic patients are due to malignancy. In the late subacute and chronic stages of benign fracture, MRI chemical-sensitive techniques such as fat-suppression or out-of-phase imaging may be helpful – benign lesions should follow normal marrow.

Red marrow reconversion may mimic metastatic lesions on routine T1 imaging. Again, chemical-sensitive techniques are useful for this. There also will be no cortical disruption and no soft tissue mass.

MRI should be performed in patients with metastases and neurological impairment for superior imaging of epidural masses and cord involvement.

Reference: Ross JS, et al. Diagnostic Imaging: Spine. Amirsys 2004.

Credit: Dr Laughlin Dawes