Spinal Cord Compression - Thoracic Metastasis
CIM Case: Spinal Cord Compression - Thoracic Metastasis
Clinical Scenario
Patient: 70-year-old man Presentation: 12-month history of progressive low thoracic back pain, now developing bilateral leg weakness over past 2 weeks Relevant history: Previously healthy, no prior malignancy, 30 pack-year smoking history (quit 10 years ago), 5kg weight loss over 6 months, no urinary or bowel symptoms (yet), no prior spine surgery Examination findings:
- Thin, cachectic man
- Point tenderness over T10-T11 spinous processes
- Lower limb examination:
- Power 4/5 bilateral hip flexors and knee extensors
- Power 3/5 bilateral ankle dorsiflexors
- Increased tone bilaterally
- Brisk knee and ankle reflexes
- Upgoing plantars (Babinski positive) bilaterally
- Sensory level at T10 (reduced sensation below)
- Anal tone intact, no saddle anaesthesia
- Gait wide-based, uses walking stick
Investigations Provided
Laboratory Results
| Test | Result | Normal Range | Interpretation |
|---|---|---|---|
| Hb | 105 g/L | 130-170 g/L | ↓ Anaemia of chronic disease |
| WCC | 9.5 ×10⁹/L | 4-11 ×10⁹/L | Normal |
| Platelets | 185 ×10⁹/L | 150-400 ×10⁹/L | Normal |
| CRP | 28 mg/L | <5 mg/L | ↑ Elevated |
| ESR | 65 mm/hr | <20 mm/hr | ↑ Elevated |
| Calcium | 2.45 mmol/L | 2.2-2.6 mmol/L | Normal |
| Phosphate | 1.0 mmol/L | 0.8-1.5 mmol/L | Normal |
| ALP | 185 U/L | 30-120 U/L | ↑ Elevated |
| Albumin | 30 g/L | 35-50 g/L | ↓ Low |
| PSA | 3.2 ng/mL | <4 ng/mL | Normal |
| Protein electrophoresis | No paraprotein | - | Excludes myeloma |
| LDH | 320 U/L | 120-250 U/L | ↑ Elevated |
| Creatinine | 95 μmol/L | 60-110 μmol/L | Normal |
Imaging
Image 1: Thoracic Spine X-ray
Radiological features:
- Collapse of T10 vertebral body
- Loss of vertebral height anteriorly
- Pedicle destruction on AP view ("winking owl" sign)
- Increased kyphosis at T10 level
- No obvious lytic lesions elsewhere on plain film
Image 2: MRI Thoracic Spine (T1, T2, STIR)
Findings:
- T10 vertebral body collapse with posterior retropulsion
- Epidural tumour extension causing cord compression
- Cord signal change at T10 level (myelomalacia)
- T1 hypointense lesion replacing normal marrow signal
- Additional lesions at T6 and L2 (not causing cord compression)
- Paraspinal soft tissue mass
Image 3: CT Chest/Abdomen/Pelvis (Staging)
Findings:
- 3.5cm spiculated mass in right upper lobe (primary lung cancer)
- Ipsilateral hilar lymphadenopathy
- Multiple small pulmonary nodules
- No liver metastases
- No adrenal metastases
- Multiple bone lesions on bone windows
Questions & Model Answers
What is the diagnosis and how urgent is this presentation?
What prognostic scoring systems would you use?
What is the role of surgery versus radiotherapy?
Describe your surgical approach.
What adjuvant treatments are required?
What is the prognosis and how would you counsel this patient?
Key Teaching Points
Pattern Recognition
This pattern suggests Metastatic Spinal Cord Compression:
- Older patient with progressive back pain
- Constitutional symptoms (weight loss, fatigue)
- Smoking history (lung cancer risk)
- Progressive neurological symptoms
- Upper motor neuron signs (hyperreflexia, Babinski)
- Sensory level on examination
Red Flags for Spinal Cord Compression:
- New back pain in known malignancy
- Progressive weakness (hours to days)
- Bladder/bowel dysfunction
- Sensory level
- Band-like chest/abdominal pain
Critical Management Points
- This is an emergency - deteriorating neurology requires urgent action
- Dexamethasone 16mg immediately on diagnosis
- MRI whole spine - 30% have multiple levels involved
- SINS score guides mechanical stability
- Tokuhashi score guides prognosis and surgical extent
- Surgery + RT superior to RT alone (Patchell trial)
- Preserve ambulation - non-ambulatory patients rarely walk again
Common Examiner Follow-ups
Q: "What is the NOMS framework?"
NOMS is a decision framework for metastatic spine disease:
| Component | Consideration |
|---|---|
| Neurological | Degree of cord compression, myelopathy |
| Oncological | Radiosensitivity, systemic disease control |
| Mechanical | Stability (SINS score) |
| Systemic | Medical fitness, expected survival |
It guides treatment selection:
- High-grade compression + instability → Surgery + RT
- Low-grade compression + stable + radiosensitive → RT alone
- Unstable + radiosensitive → Surgery for stabilisation + RT
Q: "When would you consider stereotactic body radiotherapy (SBRT)?"
SBRT considerations:
| Indication | Rationale |
|---|---|
| Radioresistant tumour (RCC, melanoma) | Higher doses overcome resistance |
| Oligometastatic disease | Potentially curative |
| Re-irradiation | Can treat previously irradiated areas |
| Post-operative | Better local control after separation surgery |
Contraindications:
- Spinal cord directly abutting tumour (need separation surgery first)
- Multiple contiguous levels
- Poor expected survival (<3 months)
Q: "What is separation surgery?"
Separation surgery is a minimally invasive approach:
- Goal: Create gap between tumour and spinal cord
- Decompress cord circumferentially
- Stabilise with instrumentation
- Allows safe delivery of SBRT post-operatively
- Not attempting gross total resection
- Reduces surgical morbidity while enabling high-dose RT
Q: "What is the role of vertebroplasty/kyphoplasty?"
Cement augmentation:
| Indication | Use |
|---|---|
| Painful vertebral metastasis | Pain relief |
| Prophylactic stabilisation | Prevent collapse |
| Augment pedicle screws | Improve fixation in poor bone |
NOT indicated:
- Epidural tumour extension (cord compression risk)
- Vertebral body posterior wall breach
- Neurological compromise
- Infection
For this patient with cord compression, open surgery is required - vertebroplasty alone is contraindicated.
Related Topics
- Metastatic Bone Disease
- Spinal Tumours
- Pathological Fractures
- Posterior Spinal Instrumentation
- Radiotherapy in Oncology
- Palliative Orthopaedics