Ch49 Tumours of the Spine and Spinal Cord

Question 1

What percentage of primary CNS tumours are intraspinal?

Answer 1

15%

Question 2

What is the relative frequency of extradural, intradural extramedullary and intradural spinal cord (Sic) tumours? (general hospital cohort)

Answer 2

Extradural 55%
Intradural extramedullary 40%
Intramedullary spinal cord tumours 5%

Question 3

Classify extradural spinal cord (Sic) tumours

Answer 3

Metastatic
Primary
Miscellaneous

Question 4

Subclassify metastatic extradural spinal tumours (two categories)

Answer 4

• osteolytic
  e.g. lymphom, lung, breast,
  prostate
• osteoblastic
  Men Prostate Ca
  Women Breast Ca

Question 5

Subclassify primary extradural spinal tumours

Answer 5

• chordomas
  
  • osteoid osteoma
  • osteoblastoma
  • aneurysmal bone cyst
  • chondrosarcoma
  • osteochondroma (most during adolescence)
  • vetebral haemangioma
  • giant cell tumours of bone (AKA osteoclastoma)
  • Giant cell graunuloma (solid variant of ABC)
  • brown tumour of hyperparathyroidism
  • osteogenic sarcoma

Question 6

Subclassify miscellaneous extradural spinal tumours

Answer 6

• plasmacytoma
• multiple myeloma
• unifocal langerhans scell histiocytosis
• Ewing’s sarcoma
• chloroma
• angiolipoma
• neurofibromas
• “Masson’s vegetant intravascular. haemangioendothelioma”!

Question 7

Classify intradural extramedullary spinal cord tumours

Answer 7

Meningiomas
Neurofibromas
Schwannomas
Lipomas
Mets (rare) (4% of spinal mets in this compartment)

Question 8

Classify intramedullary spinal cord tumours

Answer 8

astrocytoma (30%)
ependymoma (30%)
Others (30%)
- GBM
- dermoid
- epidermoid
- teratoma
- lipoma
- haemangioblastoma
- neuroma
- syrinx (not neoplastic - in Greenberg still)
Extremely rare tumours
- lymphoma
- oligodendroglioma
- cholesteatoma
- intramedullary met (2% of spinal mets)

Question 9

What are the three most common initial symptoms of spinal meningioma?

Answer 9

Pain (42%)
Motor deficit (33%)
Sensory distubance (25%)

Question 10

What percentage of spinal schwannomas arise from the dorsal rootlets?

Answer 10

75%

Question 11

What’s the epidemiology of spinal meningiomas?

Answer 11

Age 40-70 years

Female:Male ratio 4:1 overall

Question 12

Describe Asazuma’s classification for dumbbell schwannomas

Answer 12

Type 1 - intracanal - constriction at dura
Type 2 - Extradural constriction at foramen
Type 3 - Both dura and foraminal constriction (double dumbbell)
IV V and VI are very odd
Type 4 - Constriction at cortex of vertebral body
Type 5 - constriction at the intralaminar space
Type 6 - multiple sites (e.g. vertebral body cortex + foramen + lamina)

Question 13

What are the two principle fibre types in schwannoma?

Answer 13

Antoni A (compact interwoven bundles of schwanna cells)
Antoni B (sparse areas of Schwann cells in a loose eosinophilic matrix)

Question 14

When would you need a combined anterior and posterior approach for a schwannoma?

Answer 14

When extraforaminal extension is large e.g. beyond vertebral arteries

Question 15

Give reasons why deficit may not occur after nerve root/partial root sacrifice in schwannoma

Answer 15

• adjacent roots may compensate
• is is often possible to preserve some fascicles rather than sacrifice whole root
• adjacent roots may compensate

Question 16

Which has a higher rate of motor deficit schwannoma or neurofibroma

Answer 16

schwannoma

Question 17

What non neoplastic lesions are in the differential for intramedullary tumours

Answer 17

VAscular
Demyelination (normally limited to 2 vertebral levels)
Inflammatory myelitis
Paraneoplastic myelopathy
Syrinx (not in greenbergy)

(Greenberg also has disesae causing pain in certain body segments and vertebral structures e.g. paget’s)

Question 18

What percentage of intramedullary spinal cord tumours enhance?

Answer 18

91% - it does not correlate with grade

Question 19

What investigation is mandatory for ependymoma

Answer 19

Neuraxis MRI

Question 20

What percentage of patients with spinal haemoangioblastoma have VHL?

Answer 20

80%