Brain Tumor

1. See Also
   1. Brain Lesion
   2. Pediatric Brain Tumor
   3. HIV related Brain Lesion
2. Epidemiology
   1. Primary malignant Brain Tumors account for only 2% of all cancers
   2. Incidence: 6.4 cases per 100,000 person-years
   3. Age at peak Incidence for adults: 65-79 years old
   4. Lifetime Prevalence in U.S.
      1. Men: 0.65%
      2. Women: 0.5%
3. Risk Factors: Environmental (most uproven)
   1. High Dose Ionizing Radiation (Only proven risk factor)
   2. Electromagnetic field exposure (e.g. cellular phones, unproven)
   3. Head Injury (unproven)
   4. Infections (e.g. Toxoplasmosis gondii, unproven)
   5. Chemical exposures (unproven)
      1. Air Pollution from car exhaust
      2. Alcohol Abuse
      3. Hair dyes
      4. Nitrate, nitrite and nitrosamine intake
      5. Pesticides
      6. Petroleum products
      7. Solvents
      8. Tobacco abuse
      9. Vinyl Chloride
4. Risk Factors: Hereditary Condition Associations
   1. Li-Fraumeni Syndrome
   2. Multiple Endocrine Neoplasia Type I
   3. Neurofibromatosis
   4. Nevoid Basal Cell Carcinoma Syndrome
   5. Tuberous Sclerosis
   6. Turcot's Syndrome
   7. Von Hippel-Lindau Disease
5. Symptoms: Presenting
   1. Headache (70%)
      1. Often occurs in the morning
   2. Seizures (54%)
      1. Most often focal Seizures (e.g. Partial Motor Seizures)
      2. Seizures may progress to Generalized Tonic-Clonic Seizures (e.g. Jacksonian Seizure)
   3. Cognitive or Personality Changes (52%)
      1. Memory loss and decreased alertness
   4. Focal Weakness (43%)
   5. Nausea or Vomiting (31%)
   6. Speech altered (27%)
   7. Altered Level of Consiousness (25%)
   8. Visual Changes (22%)
6. Signs: Focal findings suggestive of lesion
   1. Eye exam (observe for signs of Increased Intracranial Pressure)
      1. Papilledema (present in only 5% of cases at primary tumor presentation)
      2. Cranial Nerve 6 palsy
   2. Motor Exam
      1. Focal motor weakness
   3. Coordination
      1. Gait disturbance
7. Types: Primary Brain Tumors in Adults
   1. See Pediatric Brain Tumor for Types in Children
   2. Benign
      1. Meningioma (17%)
         1. Grade 1: Meningioma
         2. Grade 2: Atypical Meningioma
         3. Grade 3: Anaplastic Meningioma (malignant)
      2. Pituitary adenoma (5%)
      3. Schwannoma (3-5%)
      4. Craniopharyngioma (<2%)
   3. Malignant
      1. Gliomas
         1. Astrocytoma (18-20%)
            1. Grade 1: Pilocytic Astrocytoma
            2. Grade 2: Diffuse Astrocytoma
            3. Grade 3: Anaplastic Astrocytoma
         2. Glioblastoma (35-40%)
            1. Grade 4: Glioblastoma
      2. Oligodendroglial Tumor
      3. Pineal Tumor (2%)
      4. Medulloblastoma (<1%)
   4. References
      1. Mahaley (1989) J Neurosurg 71: 826-36
8. Types: Metastatic Cancer to Brain
   1. Common
      1. Lung Cancer
      2. Breast Cancer
   2. Less common
      1. Hypernephroma
      2. Melanoma
      3. Prostate Cancer
9. Prognosis: Better prognostic factors
   1. Age under 60 years
   2. Seizure at presentation
   3. Cancer characteristics
      1. Low grade Brain Tumors
      2. Frontal Lobe tumors
      3. Tumor cells with low proliferative activity and tumor necrosis is absent
      4. MGMT gene promotor hypermethylation present
   4. Treatment response
      1. Minimal residual tumor post-resection
10. References
    1. Behin (2003) Lancet 361(9354):323-31
    2. Buckner (2007) Mayo Clin Proc 82(10):1271-86
    3. Chandana (2008) Am Fam Physician 77:1423-30