CNS Tumors

Question 1

Intro-Epidemiology

Answer 1

• 85% within the brain (15% SC)
• adults: 70% SUPRA-tentorial (in cerebrum)
• kids: 70% INFRA-tentorial (in the cerebelly)
• enign lesions can have fatal outcomes because of the location

Question 2

Types of Tumor Growth and Spread

Answer 2

• expansile: sharp border between tumor and surrounding tissue
• infiltrative: single tumor cells percolate through the brain parenchyma and surround nml structures
• Spread: uncommon to metastasis outsid CNS
  
  • subarachnoid space=pathway for spread of medulloblastomas
• exam CSF cytology in: metastatic carcinomas and medulloblastomas

Question 3

Clinical S&S

Answer 3

• local brain invasion
• compression of adjacent structures
• determined by tumor type and location
• HA-common manifestation due to increased intracranial pressure
  
  • also N/V, and seizures common in superficial tumors
• syncope-significant rise in ICP cut of perfusion; eg colloid cyst of 3V (by Foramen of Monroe)
• Cranial nerve palsies depend on location of the tumor
• Focal neuro deficits-weakness sensory loss, aphasia, visual spatial dysfunction
• cognitive dysfunction (white matter)
• COD: internal herniaiton and compression of vital centers-cardiac and respiratory centers in the medulla

Question 4

Classifications

Answer 4

• primary-tumors arising from brain parenchyma or its convering; classifid according to cell type of origin
  
  • most common in adults: meningioma, schwannoma, glioblastoma
  • most common in kids: pilocytic astrocytoma, ependymoma, medulloblastoma
• metastatic-secondar tumors which spread to the brain through the bloodstream (fromy systemic sources)

Question 5

Primary tumors arising in the parenchyma

Answer 5

1. Gliomas
   
   1. ASTROCYTOMA
   2. oligodendroglioma
   3. ependymoma (NON-infiltrating)
2. neuronal and mixed neuronal-glial tumors
   
   1. central neurocytoma
   2. ganglioglioma
   3. DNET
3. embryonal tumors
   
   1. medulloblastoma
   2. PNET
   3. AT/RT

Question 6

Tumors arising from the coverings

Answer 6

1. MENINGIOMA
2. Hemangiopericytoma
3. chondroma
4. leiomyoma
5. osteoma
6. hemangioma
7. lipoma

Question 7

Tumors from elsewhere

Answer 7

1. Tumors of the PITUITARY GLAND
   
   1. pituitary adenoma
   2. craniopharyngioma
2. Tumors of the PINEAL GLAND
   
   1. germinoma
   2. pineocytoma
3. Tumors of CN and Peripheral Nerves
   
   1. schwannoma
   2. neurofibroma
   3. MPNST