Medicine & USMLE


Brain Tumors
  1. Craniopharyngioma
  2. Oligodendroglioma
  3. Schwannoma
  4. Glioblastoma Multiforme (Grade IV Astrocytoma)
  5. Meningioma
  6. Ependymoma
  7. Pinealoma
  8. Pilocytic Astrocytoma
  9. Medulloblastoma
  10. Pituitary Adenoma
  11. Hemangioblastoma

Schwannomas are benign tumors most commonly found in adults. They primarily affect cranial nerves 7 and 8 at the cerebellopontine angle. This can impact any function of the facial or vestibulocochlear nerves, but schwannomas most commonly cause sensorineural hearing loss. These tumors are associated with Neurofibromatosis Type 2, where they clasically present bilaterally. Diagnosis typically involves a biopsy, and under the microcope, schwannomas stain positively for S-100. They also have a biphasic appearance on histology, which refers to hypercellular areas containing spindle cells alternating with hypocellular, myxoid areas. Surgical resection is the preferred method of treating schwannomas.