Brain tumors > Health and Wellness.

What are brain tumors?

A tumor is a set of cells that grow and multiply abnormally. Brain tumors can be primary, when they are formed from the own cells that make up the brain tissue, and metastatic, when its origin is in a tumor located in another area of the body that has spread to the brain.
Metastatic tumors are much more frequent than the primary, since between 20 and 40% of cancer patients may develop brain metastases. The incidence of tumors intracranial primary is 1-8 cases per 100,000 inhabitants per year. This incidence shows a peak in childhood, where brain tumors are the second most frequent cause of cancer after leukemia, and increases the age of 40.
The different types of tumors play a role different depending on the age of the patient. Thus, in childhood are frequent infratentorial tumors (located in the lower part of the brain) as medulloblastoma and cerebellar Astrocytoma, while adults predominate glioblastoma multiforme and anaplastic Astrocytoma (both malignant and with poor prognosis due to its high rate of recurrence after surgery). Meningioma is the most common benign primary brain tumor, and originates in the meninges, which are the layers of tissue covering the brain.

Causes of brain tumors

The causes of intracranial tumours are unknown. We know that in some types of brain tumors are important inheritance and genetic factors, but in the majority of patients there is no evidence of a family history

Symptoms of brain tumors

Brain tumors produce symptoms and neurological signs that are divided into General and focal. These symptoms vary according to the location of the tumor. Thus, the fast-growing tumors present clinical manifestations much before the slow-growing.
(Local) focal symptoms include seizures, paresis (paralysis), aphasia (difficulty to understand and produce language), apraxias (inability to perform movements), agnosias (alteration of the memory), cranial (cerebral nerves) condition, etc. These focal symptoms are produced by the tumor mass and peritumoral edema (fluid that surrounds the tumor).
General symptoms are attributed to an increased intracranial pressure. Intracranial hypertension may be produced by own tumor mass, by peritumoral edema, by obstruction of the flow of CSF (cerebrospinal fluid, in which the central nervous system is immersed), by obstruction of the cerebral venous system, or by a blockage of CSF absorption. These general symptoms include mental disorders, headaches, nausea and vomiting, dizziness, generalized convulsions and papilledema (fluid in the eye). It is also common to see alterations of the personality, headaches (sometimes night or morning dominance), dizziness and nausea, in initial stages.
In patients with intracranial hypertension are frequently symptoms and known as focal signs of false location, due to the displacement of the brain tissue of an intracranial compartment to another. The most common symptoms are: apathy (emotional indifference), urinary incontinence, and imbalance of the March, unilateral or bilateral paralysis of cranial VI, ptosis (fall of the upper eyelid of the eye), Mydriasis (dilation of the pupil), hemiparesis (paralysis of half the body) ipsilateral and bilateral Babinski (infant, abnormal reflex in adults, which consists of open fan the toes after rubbed firmly of the same plant), focal or generalized seizures, and signs of corticospinal involvement.
Other symptoms that may cause to suspect the presence of a tumor are:
  • Drowsiness and changes in alertness.
  • Difficulty swallowing.
  • Tremor of the hands.
  • Weakness, numbness or tingling on one side of the body.
  • Lack of balance and coordination in the movements.
  • Vertigo.
  • Alterations of the senses and the ability to perceive certain stimuli (temperature changes, pain...).
  • Loss of bladder or bowel control.
  • Changes in mood, personality, and behavior.
  • Problems to read or write.

Diagnosis of brain tumors

The diagnosis of an intracranial tumor is established by clinical and complementary examinations which confirm the presence of the tumor, its location, and even, at times, provide specific information about its characteristics. The most useful test is magnetic resonance imaging (MRI), which defines, as computed axial tomography (CT), the tumor itself and differentiates it from circulating edema. Other tests are angiography (test diagnostic imaging which scans blood vessels), evoked potentials (test which consists of recording and processing brain responses to different sensory stimuli), and CSF studies.
The definitive diagnosis is established with a biopsy (taking a sample of tissue for study) of the tumor, which should be (except medical indication against), even if the tumor is not susceptible of surgery.

Differential diagnosis

Intracranial tumors must be differentiated from other processes capable of producing focal neurological symptoms. Therefore, other non-tumor expansive intracranial disorders such as bleeding, should be excluded cysts, vascular malformations, etc.

Complications of brain tumors

Any other location (not brain) cancer patients often have neurological complications of the disease, which sometimes can be serious and irreversible consequences, therefore they need early diagnosis that allows them to maintain the quality of life.

Brain metastases

It consists of the extension of a cancer within the brain. It is the most common complication. Tumors that most often produce brain metastasis are lung, breast and melanoma skin cancer. Often patients with lung cancer and melanoma perform an MRI before starting treatment, in order to rule out the presence of metastases to the brain.
The clinic consists of the emergence, in days or weeks, a neurological defect (which depends on the location of the metastasis), seizures or headaches. The diagnostic method of choice is the MRI.
Brain metastases have a poor prognosis, since they indicate the presence of disseminated cancer. Depending on whether or not the primary tumor (tumor that has spread) is controlled, and the number of intracranial metastasis (single or multiple) applies a treatment or another (radiation or surgery).

Neoplastic meningitis

It consists of the involvement of the meninges (brain covers) by a systemic cancer. The most frequent causes are lymphomas and leukemias, as well as lung and breast cancer.
The clinic consists of the appearance of various symptoms, as intracranial hypertension or paralysis of cranial nerves, especially the oculomotor (responsible for the movement of the eyes), facial and the auditory.
The diagnosis is made by a CSF examination, where you will discover malignant cells.
Neoplastic meningitis does depends on the type of tumor arising from the condition, and from the moment of appearance in relation to cancer. In general, it is bad. Treatment can consist of chemotherapy and/or radiation therapy.

Cerebrovascular complications

The incidence, type, and the mechanism of cerebral vascular injury vary depending on the tumor. In general, bruising and cerebral infarcts occur. The main cause of the bruising is bleeding from the tumor metastasis, while attacks are produced by a coagulation or a thrombus.

Treatment of brain tumors

The treatment of brain cancer depends on the type, degree, the extension and the location of the tumor. The therapeutic possibilities include surgery to remove the tumor, chemotherapy and radiotherapy. It is common to use several of these techniques, combining them to obtain greater benefit against cancer. The treatment guidelines should be monitored by a medical expert.
In high-grade gliomas treatment has achieved better results and a higher rate of survival of patients, has been the combination of surgery (when possible), radiation therapy, and chemotherapy. He is recommended in these cases radiotherapy after the operation with techniques allowing to delimit the zone as much as possible to radiate to avoid damaging healthy brain tissue.
Some drugs that have demonstrated efficacy in postoperative treatment of these tumours are temozolomide, taxanes, and irinotecan.
You must be regular monitoring of patients, performing a brain resonance, every six months when it's low grade gliomas, and every three months in the high-grade. In cases in which the resonance offers questions, another test called emission tomography (PET) Positron, which consists of evaluating the behavior more or less aggressive tumor, according to the incorporation of glucose or other labelled molecules can be.
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