Skull and Spine Disorders
◊Most common vertebral tumor!
Prevalence: 510% of cancer patients
Age: usually >50 years of age
Source:
- Metastatic tumor: lung, breast, prostate (1520%) >kidney, lymphoma, malignant melanoma
- Primary tumor: multiple myeloma
Spread:
- hematogenous spread to vertebral body (bones with greatest vascularity) + epidural space
- contiguous spread from paraspinal region: lymphoma, sarcoma, lung carcinoma
- back pain; motor deficits; sensory abnormality
- autonomic dysfunction (bladder, bowel)
Location: thoracic >lumbosacral >cervical spine
Clues:
- multiple lesions of variable size
- pedicles often destroyed
- vertebral compression fracture
- associated epidural tumor
- cortical disruption (= osteolysis)
Radiograph:
- osteolytic >>osteoblastic >mixed metastases
MR (93% sensitive, 97% specific, 97% accurate):
- patchy multifocal relatively well-defined lesions
- diminished signal on T1WI on background of high-signal appearance of marrow fat
- increased signal on T2WI (except for blastic metastases with diminished T1 + T2 signals)
- contrast enhancement on T1WI (majority)
- pathologic compression fracture:
- fracture only after all vertebral body fat replaced
- hyperintense on diffusion-weighted images (DDx: hypointense benign osteoporotic fracture)
- Whole-spine MRI to search for multifocal involvement!
Risk: malignant spinal cord compression (510%)
- Metastatic extension into spinal canal can result in neurologic symptoms and paralysis.
DDx:
- Infection (centered around disk space)
- Primary vertebral tumor (rare in older patients, almost always benign in patients <21 years of age)