BRAIN TUMOR

 

  Brain tumor

  Types of brain tumors

  A brain tumor, also known as an intracranial tumor, is an abnormal mass of tissue in which cells grow and grow uncontrollably, apparently not controlled by the mechanism that controls normal cells.  More than 150 different brain tumors have been documented, but the two main groups of brain tumors are called primary and metastatic.

  Primary brain tumors are tumors that originate from brain tissue or the environment close to the brain.  Primary tumors are classified as gallbladder (containing glial cells) or non-gallbladder (brain structures including nerves, blood vessels, and glands) and benign or malignant.

  Metastatic brain tumors include tumors that grow elsewhere in the body (such as the breast or lungs) and are transmitted to the brain, usually through the blood.  Metastatic tumors are considered cancerous and are malignant.

  Metastatic tumors in the brain affect one in four patients, or an estimated 150,000 people each year.  Up to 40% of people with lung cancer will develop metastatic brain tumors.  In the past, patients diagnosed with these tumors had poor results, usually with a survival rate of only several weeks.  In addition to state-of-the-art surgical and radiation methods, more sophisticated diagnostic tools have helped increase survival rates over the years.  And after the diagnosis, a better quality of life was allowed for the patients.

  Types of benign brain tumors

  Cordomas are benign, slow-growing tumors that are most common in people between the ages of 50 and 60.  The most common areas are the base of the skull and the lower part of the spine.  Although these tumors are benign, they can invade adjacent bone and put pressure on nearby nerve tissue.  These are rare tumors, accounting for only 0.2% of all primary brain tumors.

  Craniopharyngiomas are usually benign, but they are difficult to remove due to their location near the delicate structures deep in the brain.  They are usually caused by a part of the pituitary gland (the structure that regulates many hormones in the body), so almost all patients will need some hormone replacement therapy.

  Gangliocytomas, gangliomas and anaplastic gangliogliomas are rare tumors involving neoplastic nerve cells that vary relatively well, mainly in young adults.

  Glomerular jugular tumors are often benign and usually occur just below the base of the skull, in the upper part of the jugular vein.  They are the most common form of glomerular tumor.  However, glomerular tumors, in general, contribute only 0.6% to neoplasms of the head and neck.

  Meningiomas are the most common benign intracranial tumors, comprising 10 to 15% of all brain neoplasms, although very few percent are malignant.  These tumors originate from meninges, the membrane-like structures that surround the brain and spinal cord.

  Pynocytomas are usually benign lesions caused by pineal cells, which are mainly found in adults.  They are often well-defined, non-aggressive, uniform and slow-growing.

  Pituitary adenomas are the most common intracranial tumors after gliomas, meningiomas, and schwanomas.  The vast majority of pituitary adenomas are benign and grow quite slowly.  Even malignant pituitary tumors rarely spread to other parts of the body.  Adenomas are by far the most common disease affecting the pituitary.  They usually affect people in their 30's or 40's, although they can be diagnosed in children.  Most of these tumors can be successfully treated.

  Schwannomas are common benign brain tumors in adults.  They are born with nerves, consisting of cells that normally provide "electrical insulation" for nerve cells.  Schwannomas often displace the rest of the nerve instead of attacking it.  Acoustic neuromas are the most common schwannoma, caused by the eighth cranial nerve, or vestibularcochlear nerve, which travels from the brain to the ear.  Although these tumors are unique, if they grow and put pressure on the nerves and eventually the brain, they can lead to serious complications and death.  Elsewhere with the spinal cord and, more rarely, the nerves that go to the limbs.

  Types of malignant brain tumors

  Gliomas are the most common type of adult brain tumor, causing 78% of malignant brain tumors.  They are made up of helper cells in the brain, called the gills.  These cells divide into astrocytes, epidemiol cells, and oligodendrogel cells (or oligos).  Catapult tumors include the following:

  Astrocytomas are the most common glioma, accounting for about half of all primary brain and spinal tumors.  Astrocytomas are made up of star-shaped glial cells called astrocytes, which are part of the supporting tissue of the brain.  They can be in many parts of the brain, but most are in the brain.  People of all ages can develop astrocytomas, but they are more common in adults - especially in middle-aged men.  Astrocytomas at the base of the brain are more common in children or young people and cause the majority of children's brain tumors.  In children, most of these tumors are considered low-grade, while in adults, most are high-grade.

  Ependymomas are derived from neoplastic transformation of the epidemiological cells lining the ventricular system and make up two to three percent of all brain tumors.  Most are well described, but some are not.

  Glioblastoma multiforme (GBM) is the most invasive type of glial tumor.  These tumors grow rapidly, spread to other tissues, and are poorly diagnosed.  They can contain many different types of cells, such as asteroids and oligodendrocytes.  GBM is more common in people between the ages of 50 and 70 and is more common in men than women.

  Medloblastomas usually form in the cerebellum, often in children.  These are advanced tumors, but they are usually responsible for radiation and chemotherapy.

  Oligodendrogliomas are derived from cells that make myelin, which is the insulation of brain wires.

  Other types of brain tumors

  Hemangioblastomas are tumors that grow slowly, usually in the cerebellum.  They come out of the blood vessels, can be large in size and often have cysts with them.  These tumors are most common in people between the ages of 40 and 60 and are more common in men than women.

  Rhabdoid tumors are rare, highly invasive tumors that spread to the central nervous system.  They often appear in various parts of the body, especially in the kidneys.  They are more common in young children, but can also occur in adults.

  Pediatric brain tumor

  Brain tumors in children usually come from different tissues than in adults.  Treatments that are well tolerated by the adult brain (such as radiation therapy) can prevent normal brain development in children, especially in children under five.

  According to the Pediatric Brain Tumor Foundation, approximately 4,200 children in the United States have been diagnosed with a brain tumor, of which 72% have been diagnosed with a brain tumor under the age of 15.  Of the brain).  Most children have hydrocephalus (accumulation of fluid in the brain) or the face or body does not function properly.

  Some types of brain tumors are more common in children than in adults.  The most common types of pediatric tumors are medloblastomas, low-grade astrocytomas (pylocytic), epidemiomas, craniofarangiomas, and brain stem gliomas.

  The World Health Organization (WHO) has developed a classification system for identifying tumor malformations or benign lesions under a microscope based on its histological features.

  The most deadly

  Rapid development, aggressive

  Extensive infiltration

  Rapid recurrence

  Suffering from necrosis

  World Health Organization (WHO) Brain Tumor Rates

  Grade characteristics Tumor types

  Low grade WHO grade I.

  The least lethal (benign)

  Possibly treatable by surgery alone

  Non-intrusion

  Long term survival

  Grow slowly

  Pylocytic astrocytoma

  Craniopharyngioma

  Gangliocytoma

  Ganglioglyoma

  WHO Grade II

  Grow relatively slowly

  Some intrusion

  Repeat as advanced

  "Diffuse" Astrocytoma

  Pineocytoma

  Pure oligodendroglioma

  High grade WHO grade III

  lethal

  Intruder

  The tendency to re-emerge as advanced

  Anaplastic astrocytoma

  Anaplastic epidemioma

  Anaplastic oligodendroglioma

  WHO Grade IV

  The most deadly

  Raid growth, aggression

  Extensive infiltration

  Rapid recurrence

  Suffering from necrosis

  Gliobastoma multiforme (GBM)

  Pineoblastoma

  Medloblastoma

  Ependymoblastoma

  Incidents in adults

  The National Cancer Institute estimates that 22,910 adults (12,630 men and 10,280 women) will be diagnosed with brain and other nervous system tumors in 2012.  It also estimates that 13,700 of these diagnoses will lead to death in 2012.

  Between 2005 and 2009, the average age of death from cancer of the brain and other areas of the nervous system was 64 years.

  Causes of brain tumors

  Brain tumors are formed when certain genes on a cell's chromosome are damaged and do not function properly.  These genes typically regulate the rate at which a cell divides (if it divides completely) and repair genes that repair defects in other genes, as well as genes that make up the cell.  Cause self-destruction if the damage is beyond repair.  In some cases, an individual may be born with partial defects in one or more of these genes.  Environmental factors can then cause further damage.  In other cases, environmental damage to the genes may be the only cause.  It is not known why some people develop brain tumors in the "environment", while others do not.

  Once a cell divides rapidly and internal mechanisms to monitor its development fail, the cell may eventually grow into a tumor.  Another line of defense could be the body's immune system, which will better detect and kill the abnormal cell.  Tumors can produce substances that prevent the immune system from recognizing abnormal tumor cells and eventually overcome all internal and external barriers to its growth.

  A rapidly growing tumor may require more oxygen and nutrients than the local blood supply for normal tissue.  Tumors can produce substances called angiogenesis factors that promote the development of blood vessels.  As new vessels grow, they increase the supply of nutrients to the tumor, and eventually, the tumor becomes dependent on these new vessels.  Research is being done in this area, but more extensive research is needed to translate this knowledge into possible treatments.

  Symptoms

  Symptoms vary depending on the location of the brain tumor, but the following can occur with different types of brain tumors.

  Headaches that may be more severe in the morning or may wake the patient at night.

  Seizures or convulsions

  Difficulty thinking, speaking or expressing

  Personality changes.

  Weakness or paralysis of one part of the body

  Loss of balance or dizziness.

  Vision change

  Hearing changes

  Numbness or tingling of the face

  Nausea or vomiting, difficulty swallowing

  Confusion and suspicion.

  appraisal

  Advanced imaging techniques can detect brain tumors.  Diagnostic tools include computed tomography (CT or CAT scan) and magnetic resonance imaging (MRI).  Other MRI configurations can help the surgeon plan tumor resection based on the location of the normal nerve pathways in the brain.  Interactive MRI is also used during surgery for tissue biopsy and tumor removal.  Magnetic resonance spectroscopy (MRS) is used to examine the chemical profile of the tumor and to determine the nature of the lesions visible on MRI.  Positron emission tomography (PET scan) can help detect recurrent brain tumors.

  Sometimes a biopsy is the only way to diagnose a brain tumor.  The neurosurgeon performs a biopsy and the pathologist makes a final diagnosis, determines whether the tumor is benign or malignant, and classifies accordingly.

  Treatment of brain tumors

  Brain tumors (whether primary or metastatic, benign or malignant) are usually treated with surgery, radiation, and / or chemotherapy - alone or in combination.  While it is true that radiation and chemotherapy are used more frequently for malignant, residual or recurrent tumors, the decision as to which treatment to use is made on a case-by-case basis.  And it depends on many factors.  There are risks and side effects associated with each type of therapy.

  Surgery

  It is generally accepted that complete or almost complete surgical removal of a brain tumor is beneficial to the patient.  The neurosurgeon's challenge is to remove as many tumors as possible, without damaging the brain tissue that is important for the patient's neural function (such as speech, ability to walk, etc.).  Traditionally, neurosurgeons open the skull with a craniotomy to make sure they can access the tumor and remove it as much as possible.  During surgery, a drain (EVD) may be left in the cerebrospinal fluid to drain normal cerebrospinal fluid, as the brain recovers from the surgery.

  Another procedure that is usually performed, sometimes before a craniotomy, is called a stereotactic biopsy.  This small operation allows doctors to obtain tissue to make an accurate diagnosis.  Typically, a frame is attached to the patient's head, a scan is obtained, and then the patient is taken to the operating area, where a small hole is made in the skull to reach the abnormal area.  Accessible  Depending on the location of the wound, some hospitals may perform the same procedure without the use of a frame.  A small sample is obtained for examination under a microscope.

  Computerized devices called surgical navigation systems were introduced in the early 1990's.  These systems help neurosurgeons guide, localize, and familiarize tumors.  This information reduced the risks and improved the extent of tumor removal.  In many cases, surgical navigation systems have allowed excision of previously unused tumors with acceptable risks.  Some of these systems can also be used for biopsies without attaching a frame to the skull.  One limitation of these systems is that they use pre-surgery scans (CT or MRI) to guide neurosurgeons.  Thus, they cannot calculate the brain movements that may occur during the operation.  Investigators are developing techniques using ultrasound and performing surgery on MRI scanners to help update navigation system data during surgery.

  Interactive language mapping is considered by some to be a very important technique for patients with tumors that affect language function, such as large, dominant hemispherical gliomas.  The procedure involves mapping the anatomy of a conscious patient's operation and their language function during the operation.  The doctor then decides which part of the tumor is safe to resect.  Recent studies have shown that cortical language mapping can be used as a safe and effective adjunct to improve glioma resection while preserving essential language sites.

  Ventriculoperitoneal shunting may be required for some patients with brain tumors.  Everyone has cerebral spinal fluid (CSF) inside the brain and spinal cord that circulates slowly all the time.  If this flow is blocked, the sacs containing the fluid (ventricles) become enlarged, which increases the pressure inside the head, resulting in a condition called hydrocephalus.  If left untreated, hydrocephalus can cause brain damage and even death.  The neurosurgeon may decide to use a shunt to remove the spinal fluid from the brain and therefore reduce the pressure.  The body cavity in which the CSF is twisted is usually the peritoneal cavity (the area around the abdominal organs).  The shunt is usually permanent.  If it is blocked, the symptoms are similar to the actual condition of hydrocephalus and may include headache, vomiting, visual problems and / or confusion or lethargy.  Another method that can be used to control the obstruction of the cerebrospinal fluid is called Endoscopic Third Ventriculostomy.  This helps the brain to move moisture around the barrier without the need for a shunt.

  Radiation therapy

  Radiation therapy uses high energy X-rays to kill cancer cells and abnormal brain cells and shrink the tumor.  If the tumor cannot be effectively treated with surgery, radiation therapy may be an option.

  Standard external beam radiotherapy uses a variety of radiation beams to provide regular coverage of the tumor while restricting the dose to the surrounding general structure.  The risk of long-term radiation injury from modern transmission methods is very low.  New delivery techniques other than 3-dimensional conformal radiotherapy (3DCRT) include intensively modulated radiotherapy (IMRT).

  Proton beam treatment uses a specific type of radiation in which the proton, a form of radiation, specifically leads to the tumor.  The benefit is that less tissue is damaged around the tumor.

  Stereotactic radio surgery (such as gamma knife, novice and cyber knife) is a technique that focuses radiation on the target tissue with many different beams.  This treatment reduces the damage to the tissues adjacent to the tumor.  Currently, one delivery system is superior to another in terms of medical results, and each has its own advantages and disadvantages.

  Chemotherapy

  Chemotherapy is generally considered to be effective in children with specific tumors, lymphomas and some oligodendrogliomas.  Although chemotherapy has been shown to improve the overall survival of patients with the most malignant primary brain tumors, it occurs in only 20% of all patients, and physicians cannot easily estimate that  Which patients will benefit first?  Thus, some physicians choose not to use chemotherapy because of possible side effects (lung scarring, immune system suppression, nausea, etc.).

  Chemotherapy works by repairing damaged cells that are better repaired than normal tissue by tumor tissue.  Resistance to chemotherapy may include survival of tumor tissues that do not respond to medication, or failure to transfer drugs from the bloodstream to the brain.  There is a special barrier between the blood flow and the brain tissue called the blood-brain barrier.  Some investigators have tried to improve the effectiveness of chemotherapy by removing this barrier or by injecting drugs into the tumor or brain.  The second class of drugs is not intended to kill tumor cells but to prevent further tumor growth.  In some cases, growth modifiers (such as Tamoxifen, a breast cancer treatment drug) have been used to try to stem the growth of other resistant tumors.

   In 1996, the US Food and Drug Administration approved the use of chemotherapy-infected wafers, which neurosurgeons may apply during surgery.  Wafers slowly expel the drug into the tumor, and the patient receives chemotherapy with systemic side effects of treatment.

   Laser Interstitial Thermal Therapy (LITT)

   Laser thermal ablation is a new technique that some centers are using to treat small tumors, especially in areas that may be more difficult to reach using previous open surgery procedures.  This involves placing a small catheter inside the wound, possibly completing a biopsy, then using a laser to remove the wound thermally.  This technique has only recently been used in the treatment of brain tumors, so its long-term efficacy has not been established.