Brain Tumors

Neurons or Glial cells?

Neurons

• Rarely, if ever responsible for tumors – Don’t reproduce

Gliomas arise from glial cells

• Different types of gliomas:– Astrocytic tumors include astrocytomas (less

malignant), anaplastic astrocytomas, and glioblastomas (most malignant)

– Oligodendroglial tumors vary in malignancy – Glioblastomas are the most aggressive type of primary

brain tumor

Meningiomas

• Arise from arachnoidal cells– One of three meniges that compose membrane that

covers brain and spinal cord. However, these tumors are mostly (90%) benign

Level of severity

• Tumors are graded on multiple factors:– Growth rate– Blood supply– Malignancy– Border distinctness *The ultimate determining factor in classifying

tumors is the cell of highest malignancy, even if the overall composition of the tumor is of lesser malignancy.

Diagnosis

• Balance, vision, hearing, and reflex tests are conducted to help diagnose brain tumors

• MRI’s used with contrast dye are subsequently performed to find tumors and detect their locations.

Treatment

• Open cranial surgery• Radiosurgery

– Many beams of targeted radiation focus on the tumor from all different directions (one session limit).

• Radiotherapy (multi-session)• Chemotherapy

What causes a tumor?

• We don’t know yet…• But:

– 5% arise from genetic inheritance (usually extra copies chromosome 7)

– Environment also plays a role

Bibliography• http://www.willamette.edu/~gorr/classes/cs449/figs/neurons.jpg• http://www.mayoclinic.org/metastatic-brain-tumors/• http://www.irsa.org/metastatic_tumors.html• http://www.irsa.org/astrocytoma.html• http://www.nlm.nih.gov/medlineplus/ency/article/007222.htm• http://psychology.about.com/od/biopsychology/f/neuron01.htm• http://encefalus.com/wp-content/uploads/2008/09/neuron_2.jpg• http://sakshat.amrita.ac.in/VirtualLab/images/neuron.png• http://tuberose.com/Graphics/brain%20tumor.jpeg• http://www.wired.com/images_blogs/wiredscience/2009/04/neurons1.jpg