Brain Tumors Lecture Summary

May 27, 2025

Lecture on Brain Tumors

Overview

  • Brain tumors can be categorized into tumors of adulthood and tumors of childhood.
  • Important for medical examinations like USMLE.
  • Use mnemonics to simplify and remember key facts about each type.

Tumors of Adulthood

1. Glioblastoma Multiforme (GBM)

  • Highly malignant and invasive.
  • Typically crosses the corpus callosum, creating a "butterfly appearance" in the brain.
  • Histology: Pseudopalisading tumor cells, GFAP (glial fibrillary acidic protein) positive.
  • Mnemonic: GBM - G for GFAP positive, P for Pseudopalisading, M for Midline/Malignant.

2. Oligodendroglioma

  • Histology: Chicken-wire capillary pattern, "Fried egg" appearance of cells, often calcified.
  • Mnemonic: Oligo - Chicken-wire (chickens lay eggs), Fried egg appearance, Eggs have calcium (calcification).

3. Meningioma

  • Benign, superficial location (arises from meninges).
  • Histology: Psammoma bodies, spindle cells.
  • Mnemonic: MEN have problems with PSA - P for Psammoma bodies, S for Spindle cells, A for Arachnoid origin.

4. Hemangioblastoma

  • Blood vessel origin, EPO producing (can cause polycythemia).
  • Associated with von Hippel-Lindau syndrome.
  • Mnemonic: Heme (blood) Angio (vessel) Blastoma.

5. Pituitary Adenoma

  • Types: Lactotroph (prolactinoma), Somatotroph (e.g., GH, TSH, ACTH producing), Non-functional.
  • Symptoms:
    • Prolactinoma: Galactorrhea, Amenorrhea, Gynecomastia, Decreased libido.
    • Somatotroph adenomas produce symptoms based on the hormone secreted (e.g. Gigantism for GH, etc.).
    • Non-functional: Mass effect symptoms like headache, bitemporal hemianopia.
  • Mnemonic: Add-enoma - adding hormones or mass effect.

6. Schwannoma

  • Located at cerebellopontine angle, affecting CN VII (facial) & CN VIII (vestibulocochlear).
  • Histology: S-100 positive.
  • Associated with neurofibromatosis type II if bilateral.
  • Mnemonic: SCHW - S for S-100, C for Cerebellopontine, H for Hearing, W for Winking.

Tumors of Childhood

1. Pilocytic Astrocytoma

  • Histology: Rosenthal fibers, GFAP positive.
  • Mnemonic: Houston Astros (Astrocytoma) represented by Drew Rosenhaus (Rosenthal fibers).

2. Medulloblastoma

  • Histology: Homer-Wright rosettes.
  • Mnemonic: Blast the ball for a homerun (Homer-Wright rosettes).

3. Ependymoma

  • Histology: Perivascular pseudorosettes.
  • Mnemonic: Forgot mom's birthday, give a pseudo-rosette to make up (Append-a-momma).

4. Craniopharyngioma

  • Remnants of Rathke's pouch.
  • No mnemonic, just memorize association.

5. Pinealoma

  • Causes Parinaud syndrome.
  • Mnemonic: P for Pinealoma, P for Parinaud syndrome.

Additional Notes

  • Childhood tumor buzzwords are crucial for exams but less in-depth understanding is required unless pursuing neurology.
  • High-yield associations and mnemonics can greatly aid in memorization for exams.
  • The lecture emphasizes simplification through mnemonics and understanding key histological features.