brain tumors - cancer bio

What are three main parts of the brain?

cerebrum, cerebellum, brain stem

What are 4 lobes of the cerebrum?

frontal, parietal, temporal, occipital

Describe white vs. gray matter.

Gray matter is mostly the cortex and consists of high density of cell bodies, nuclei, of many neurons. 

The white matter is mostly axons, the white matter track, myelin lipid coverings of the neurons.

What cell is the functional unit of the nervous system?

neuron, nerve cell

List the glial, or supporting cells, of the CNS. List the primary function or characteristic of each cell type as well.

Astrocyte - provide physical and metabolic support for neurons

oligodendrocytes - form the myelin;

microglia - resident immune cells of the brain (macrophages, phagocytic cells)

ependymal cells - line the ventricles of the brain and central canal of the spinal cord.

What are the meninges?

connective tissue coverings of the brain

List the three layers of meninges and location/characteristic of each.

dura mater - tough mother - outermost thickest and toughest layer

arachnoid layer - lies beneath the dura - contains CSF cushion

Pia mater - delicate layer resting directly on the surface of the brain and spinal cord - tender mother.

What is the cell of origin for astrocytoma and meningioma tumors?

astrocyte (glial cell) and meninges cells

Describe the difference between primary brain tumor and secondary brain tumor.

Primary brain tumors starts in the brain, from brain cells, can be malignant, and rarely metastasize outside of the CNS;

Secondary brain tumors - metastasized to the brain from a primary site elsewhere in the body; lung breast and melanoma frequently metastasize to the brain.

What is the most common tumor found in the brain?

secondary (metastatic) tumor

What is the most common primary tumor found in the brain?

meningioma

What is the most common primary malignant tumor found in the brain?

glioblastoma

Meningioma, the most common primary tumor in the brain, if more often found in women or men?

women

Meningiomas are mostly benign or malignant?

benign

Describe the cell/location or origin of meningiomas?

tumor arises in the meninges, the coverings outer layer of the brain

List symptoms of meningioma

Headache, Seizures, Changes in vision, Fatigue, Smell or language issues

What are risk factors for meningioma?

Radiation treatment (previous); Female hormones; Inherited syndromes/mutations such as neurofibromatosis; Obesity

What are treatments for meningiomas?

Surgery often curable; Chemo/Radiation if malignant (rare)

What are psammoma bodies?

calcifications with concentric rings on microscopy histology images of some meningiomas

What makes meningiomas usually benign?

Special anatomy characteristics? Most are easily separable from the underlying brain and most do not invade into the brain.

What is the most common malignant primary tumor in the brain?

glioblastoma

What is the cell of origin of glioblastoma (GBM)?

glial cell - astrocyte

What is the median survival for glioblastoma?

12-15 months

What are histological/anatomy characteristics of glioblastoma?

Very invasive, hypoxic, necrotic core, and angiogenic

What is standard treatment for glioblastoma?

surgery, radiation, chemotherapy, and optional optune/novacure tumor treating fields magnetic cap

What patient demographics are GBM more common?

men, white (median age at diagnosis 64, which was not in lecture).

Grade 4 astrocytomas are now called astrocytoma and GBM based on what genetic mutation?

IDH mutation are typically younger and have better prognosis

What is a defining visual characteristic on MRI of GBM?

ring enhancing lesion; gadolinium contrast agent leaks out and is bright at leading edge due to vascular leaky angiogenic growth at proliferative leading edge

List some symptoms of GBM.

Headache; Seizure; Personality Changes; Motor issues; Sensory issues; Symptoms can depend on location

What are risk factors for GBM?

Previous radiation treatment; Familial germline mutation syndromes such as Li-Fraumeni

What is 5-ALA and why is it used during GBM surgery?

5-ALA (5-aminolevulinic acid) –fluorescent dye that will be taken up by tumor – helps guide surgery removal.

What is the 5 year survival for GBM?

7%