Brain Cancer

There are several types of primary brain cancers that occur in adults. This paper will focus on those that occur primarily in the cerebrum, the largest part of the brain.

Grading System
Brain tumors are graded from I to IV.

1. Grade I: Tumors classified has Grade I are low-grade tumors that grow very slowly. Often, people you have a Grade I tumor are thought to have been born with it. Grade I tumors are sometimes considered to be benign tumors.
2. Grade II: These tumors also grow very slowly. However, they do have a greater tendency to recur and to spread into nearby tissue.
3. Grade III: Grade III tumors grow rapidly. It is very likely to spread. Under a microscope, Grade III cells look very much different from normal cells.
4. Grade IV: Grade IV tumors grow and spread very rapidly, often causing a midline shift. They grow so fast that they grow faster than their blood supply can support. Therefore, Grade IV brain cancers often have areas of necrotic cells. Treatment options are few and often prognosis is poor.

Astrocytomas
Astrocytes are a type of glial cell so sometimes cancers formed from Astrocytes are called gliomas. The astrocytes, as well as other glial cells, are the structural cells of the brain. Like the iron work of a building, astrocytes serve as the structure of the cerebrum. There are a number of subtypes of Astrocytomas based on where they occur.

1. Diffuse Astrocytomas (Grade II): Although Diffuse Astrocytomas grow slowly, they do tend to spread into nearby tissue. They also often change into higher grade tumors. Astrocytomas can occur in any part of the brain but usually occur in the cerebrum.
2. Anaplastic astrocytoma (Grade III): Anaplastic tumors grow rapidly. They also will spread into nearby areas. It is common for Anaplastic tumors to change over time into Gliobastomas (Grade IV) tumors. Anaplastic astrocytoma is abbreviated "AA" in most forums.
3. Gliobastomas (Grade IV): A glioblastoma grows extremely fast. An MRI of an advanced glioblastoma often looks like an octopus with arms reaching out in all directions. Gliobastomas are also known as Glioblastoma multiforme (GBMIV). Gliobastomas are rare in children and young adults. Prognosis is poor.

Oligodendroglioma Tumors
Another type of glial cells that help maintain a healthy brain are the oligodendrocytes. Since oligodendrocytes are also glial cell, cancer formed from them are also called gliomas.

• Oligodendroglioma (Grade II): An Oligodendroglioma grows and spreads slowly. Under a microscope, the Oligodendroglioma cells look almost like normal oligodendrocytes. They are given a classification of Grade II because they to spread and they do tend to upgrade with time.
• Anaplastic Oligodendroglioma (Grade III): Cells of an Anaplastic Oligodendroglioma look significantly different from normal Oligodendrocytes. Unlike Astrocytomas, an Anaplastic Oligodendroglioma can either grow in one spot or in many spot in the brain.

Mixed Gliomas
A Mixed Glioma is quite literally formed from a mixture of astrocytes and oligodendrocytes and therefore shares characteristics of both.

• Oligoastrocytoma (Grade II): These tumors are slow growing and slow spreading tumors. The cells look almost like normal ones.
• Anaplastic Oligoastrocytoma (Grade III): Cells of an Anaplastic Oligoastrocytoma show significant changes from normal ones.

Some doctors use the term "Mixed Grade Gliomas" to characterize gliomas that contain 2 or more grades.

Pineal Parenchymal Tumors
A Pineal Parenchymal tumor is formed by parenchymal cells also called pineocytes. They often occur in adults and are relatively rare. They are divided into:

• Pineocytomas (Grade II): This is a slow growing tumor that rarely occurs in children.
• Pineoblastomas (Grade III): Pineoblastomas do spread. These tumors are rare and are more common in children.

Although there are many other types of brain cancers, these are the major ones.

Causes
Although there is not a one to one correlation between anything and brain cancer, there are some know risk factors. Here is a list of a few of the most common ones:

• Exposure to vinyl chloride
• Exposure to radiation
• Infection by the Epstein-Barr virus
• Genetic syndromes like Neurofibromatosis and Tuberous sclerosis.

Symptoms
Although symptoms vary from one individual to the next and are affected by type, size, and location of the tumor, there are some communalities:

• Seizures
• Morning headaches (not the most common one, so do not panic)
• Frequent nausea and vomiting
• Dysfunction in vision, hearing or speech
• Weakness on one side of the body
• Balance problems
• Personality changes

Diagnostic Tests

• x-Ray. Often, the first and quickest test done is an x-Ray of the head. If an abonormality is found, the x-Ray will be followed by other scans.
• CT Scan: A CAT Scan, or Computed Tomography, is an imaging technique using X-Rays to produce a three dimensional image of an organ.
• MRI: An MRI, or Magnetic Resonance Imaging, is an imaging technique that uses a strong magnetic field rather than X-Rays. It takes advantage of the magnetic properties or water atoms in the body. Under a strong magnetic field, those atoms will align themselves with the magnetic field. This technique is also called NMRI (nuclear magnetic resonance imaging). An MRI produces a great contrast between soft tissues in the body so is ideal for brain scans.
• Genetic Testing: More and more doctors are ordering genetic tests. There are several gene mutations that are either useful in diagnosis or in treatment option decisions.
• Angiogram: An Angiogram is used to study the blood flow to the tumor. This is important in making a prediction of how fast the tumor might be able to grow and in decisions about doing surgery.
• Biopsy: The only way to be 100% sure of a diagnosis is by examining under a microscope a sample of the abnormality. While this procedure is invasive, it is not very dangerous and almost always conducted. Most people recover very quickly with few if any side effects.

Prognosis
Prognosis is a statistical estimate of the chance that a person will recover or go into remission. Some factors that affect the prognosis are:

• Specific type and grade of the tumor
• Specific location of the tumor
• Size of the tumor
• Whether or not a significant part of the tumor can be surgically removed.
• Whether or not the 1p/19q genes are deleted.
• Whether or not the tumor is a recurrence of a previous tumor
• Other health problems the patient might have

Treatment Options
There are three basic types of treatment available to patients with brain cancers:

• Surgery: When surgery is possible, it should be strongly considered. It is the best way to remove a significant portion of the tumor. From the patients perspective, compared to other surgeries brain surgery is painless and easy. Recovery is usually in less than one week� often 5 days.
• Radiation Therapy: Sometimes miss identified as �radio therapy�, Radiation Therapy (RT) involves irradiating the brain or part of it with some type of radiation. There are several ways of doing this. The particular option chosen depends on the size and location of the tumor or area of concern. The total amount of radiation that a brain can receive during the live time of the patient is limited. This limit needs to be taken into account when making treatment decisions.
  1. Whole Brain Radiation Therapy (WBRT): As the name implies, involved irradiation of the whole brain. It is not often used with primary brain cancers.
  2. Steriotachtic Radiation: These are several forms of this therapy. All of them involve use of just a beam of radiation aimed only at the tumor or tumor bed. Since the medical team can aim the beam from different directions, it is possible to use lower level of radiation. Aimed at the tumor, this limits the amount of radiation to other parts of the brain. Maximum dosage is delivered where the beams cross at the tumor.
  3. Internal Radiation Therapy: This procedure involves using a catheter to place small radiation "seeds" into the middle of the cancer. Since the patient is radioactive as long as those seeds are present, the patient is placed in isolation making it impossible for family and friends to visit.
• Chemotherapy: There are a number of oral and IV medications that can be used to treat brain cancers. The major problem is that many chemicals used for other cancers will not cross the brain-blood barrier. Special chemotherapy agents have been developed in order to do so. Newer chemotherapies are being developed all the time. Older ones are being combined in new ways to improve the overall effectiveness.

One very exciting new form of cancer therapy is genetically designed agents. The Human Genome Project completed in 2003 is being used to study genetic differences between normal brain cells and cancerous cells. These differences offer the hope of targeted agents that will only kill cells that have those mutations.

Another promising treatment for GBMIV's are called "Antiangiogenic Agents" that work by hindering the growth of blood vessels. At least on of these is in the clinical trials phase.

Please use this information only for a beginning point for discussions with your own medical team.