A brain tumor is any mass created by an abnormal and uncontrolled growth of cells either found in the brain (neurons, glial cells, epithelial cells, myelin producing cells, etc.) or spread from elsewhere (metastasis). Brain tumors are usually located in the posterior third of the brain in childhood and in the anterior two-thirds of the brain in adulthood.
In the United States in 2000, it was estimated that there were 16 500 new cases of brain tumors, which accounted for 1.4% of all cancers, 2.4% of all cancer deaths, and 20%-25% of pediatric cancers. Ultimately, it is estimated that there are 13 000 deaths/year as a result of brain tumors.
brain tumor symptoms and differentiation
Tumors in the brain are either benign or malignant and each has different brain tumor symptoms.
Benign brain tumors include:
- pituitary adenoma - The diagnosis is generally entertained either on the basis of visual difficulties arising from the compression of the optic nerve by the tumor, or on the basis of manifestations of excess hormone secretion: the specifics depend on the type of hormone. Tumors which cause visual difficulty are likety to be macroadenomas greater than 10 mm in diameter; tumors less than 10 mm are microadenomas.
- meningioma - The symptoms depend closely on the exact location of the tumor. Hence, a meningioma compressing the frontal lobe can give rise to frontal lobe syndrome.
- acoustic neuroma - Associated symptoms are unilateral sensorineural hearing loss/deafness and vertigo, while larger tumors can compress local structures, such as the facial nerve, and lead to local symptoms, such as hydrocephalus.
Malignant brain tumors include:
- glioma (60% of new cases) - Brain tumor symptoms of gliomas depend on which part of the central nervous system is affected. A brain glioma can cause headaches, nausea and vomiting, and cranial nerve disorders as a result of increased intracranial pressure. A glioma of the optic nerve can cause visual loss. Spinal cord gliomas can cause pain, weakness or numbness in the extremities. Gliomas do not metastasize by the bloodstream, but they can spread via the cerebrospinal fluid and cause "drop metastases" to the spinal cord.
- glioblastoma multiforme (WHO Grade IV glioma) - Common brain cancer symptoms of the disease include seizure, headache, hemiparesis, and personality change.
Some lesions can mimic tumors of the central nervous system. These include tuberculosis of the brain and cerebral abscess.
primary brain tumors
Primary brain tumors are those tumors that originate in the brain, and are named for the cell types from which they originated. Frequently encountered histologic brain tumor types are glioma, glioblastoma, astrocytoma, oligodendroglioma, medulloblastoma, meningioma and neuroglioma. Tumors can be benign and are usually, but not necessarily, localized to a small area. They can also be malignant and invasive (i.e., spreading to neighbouring areas). Brain cells can be damaged by tumor cells by (i) directly being compressed from growth of the tumor; (ii) indirectly being affected from inflammation ongoing in and around the tumor mass, (iii) brain edema (swelling); or (iv) increased pressure in the skull (due to brain edema or to the blockage of the circulation of the cerebrospinal fluid).
Local tissue damage (either by direct or indirect mechanisms) causes focal neurologic symptoms, which vary due to the location of the brain tumor. Hemiparesis, aphasia, difficulty speaking, ataxia, hemihypoesthesia (numbness and decreased sensation of touch on one side of the body) and localized headache are some of the symptoms occurring due to the local effects of the brain tumor. Increased pressure in the skull or brain edema cause more generalized symptoms like generalized headache, nausea and vomiting, loss of consciousness (stupor or coma) and intellectual decline. Seizures due to the local irritating effect of the brain tumor or metabolic changes caused by the cancer are also frequently observed. Since the development of the skull is incomplete during infancy, infants with brain tumor may have increased head perimeter, bulging fontanelles or separated sutures.
Neurologic examination reveals local (specific to the location of the tumor) or generalized neurologic changes. Slowly progressive nature of the neurologic symptoms is suggestive of a possible brain tumor and the diagnosis is confirmed by CT scan or magnetic resonance imaging (MRI) of the head. Angiography, electroencephalography (EEG) or brain biopsy may aid in diagnosis in difficult cases. Although slow progression is an important hallmark of the disease, some brain tumors may enlarge very quickly and thus may cause sudden neurologic changes. Treatment includes the surgical removal of the tumor mass or the destruction of the tumor cells by radiation (radiotherapy) and/or drugs (chemotherapy) in cases with contraindications for a surgical operation.
secondarie brain cancer
Secondary or metastatic brain tumors take their origins from tumor cells which spread to the brain from another location in the body. They are more frequent than primary brain tumors, and are mainly a problem in adults, though children may also have secondary tumors. Approximately one quarter of metastatic cancers spread to brain. Lung cancer and breast cancer are the most common causes of secondary brain tumors. Tumor cells may travel to the brain by blood vessels. Since the brain has no lymphatic drainage system like other organs (cerebrospinal fluid system acts like lymphatic system in the brain), spreading of tumor cells by the lymphatic route (which is very typical for cancers of other organs) is impossible in the brain. In contrast to primary brain tumors, metastatic tumor masses may occur in various remote locations in the brain. Highly aggressive brain tumors like glioblastomas may also be observed in more than one location, but usually in the advanced stages of the disease. Symptoms, diagnosis and treatment are quite similar to those of primary tumors, however in the case of secondary tumors the initial location of the tumor cells must be identified and treated as well.
Primary or secondary, brain tumors may cause herniation of the brain (displacement of one part of the brain tissue due to mass effect of a lesion, usually causing the compression of the neurons controlling the respiratory system in the brainstem and eventually death) and permanent neurologic changes including intellectual decline.
Tumors located in distant locations may affect the nerve cells and cause neurologic changes by mechanisms other than direct invasion of brain tissue. Diseases caused by the remote effects of tumor cells are called paraneoplastic diseases. Tumors may affect brain cells from a distance by consuming too much food and energy that is crucial for neurons, by secreting endocrine substances altering nerve cell functions or – in the majority of the cases – by causing the immune system of the body to develop antibodies (autoantibodies) directed against nerve cells. In the latter mechanism, antibodies developed to kill tumor cells are suggested to accidentally (probably due to molecular similarities between tumor cells and normal nerve cells) bind neurons and destroy them. Paraneoplastic diseases due to autoantibodies are not confined to brain cells (e.g. Lambert-Eaton myasthenic syndrome). Most frequent paraneoplastic diseases are cerebellar ataxia, peripheral sensory neuropathy, limbic encephalitis and brainstem encephalitis. The neuroimaging studies are usually not helpful in paraneoplastic diseases and diagnosis is established by immunological methods.
Posted by Staff at May 17, 2005 4:37 AMblog comments powered by Disqus
I have a question, my sister in law just found out she has a brain tumor the only why she felt different was she lost her hering in one of her ears. and a ct scan was done. what kind of tumor would this be and is it a short term or a long term tumor.
Posted by: sally at January 4, 2006 8:12 AM
my friend complains of headaches vertigo and numbness in his fingers.should he get an MRI done, could these possibly be symptoms of a tumor?
Posted by: hoori at February 16, 2006 8:52 AM
i get some really bad headaches, sometimes i cannot formulate my words and form a proper sentence and i remember once i couldn't see in one eye for like ten minutes. i most times feel nauseated, and depressed. is this a normal migraine or are thesesigns of a possible brain tumor?
Posted by: jas at March 21, 2006 6:37 PM
My mother just called me. She said she has been getting lots of bad headaches. She took Advil, Tynolel etc. and nothing is working. Her hair is falling out on the sides & in the middle of her head. He shoulders hurt really bad, she can bearly move them. Is these sign, of a tumor?
Please let me know ASAP. I'm very worried!
Posted by: jay at April 13, 2006 6:05 PM
I feel lethargic at times, I feel outside myself like I'm just going through the motions of the day. I have severe migraines and vomit from them early in the moring and sometimes wake up from them in the middle of the night. These are usually caused by strong smells, perfume, cigrette smoke, etc. I have migraine medician. I went to my doctor and had a CT scan it showed up negitive but, I'm allergic to Iodine, so I'm not sure it showed up right. I have pain in the back of my head. I have bad dreams and sometimes feel congested as if my brain is swelling. I have trouble remembering things-short term and consentrating. Could this be a brain tumor?
Posted by: Sam at April 24, 2006 9:00 PM
I feel dizzeness and headaches for long days,lost my appettite in eating and feel weak and some pain on my neck and feel some pain after i eat and want to vomit but cannot vomit out.
Posted by: Nilda Lawas at July 21, 2006 2:31 PM
things started out with pain in my shoulder.. then progressed to pain in inner and outer aspects of my arm sometimes down to my hand migraines now, very bad with vomiting. this has all happened within a 4 month period.. got any suggestions.. cant lift the affected arm over my head at all.
Posted by: carolynpatterson at August 21, 2006 7:47 AM
My father died of a brain tumor. My maternal grandmother had parkinston. I have previously had severe migraines. I have had alot of memory loss and it is hard for me to carry on a conversation because of my memory. I am having alot of dizzy spells and alot of ringing in my head. I have been on antidepressants and anti-seisure meds. But they are taking me off right now trying to figure out what is wrong with me. Can you please give me any advise to follow up on?
Posted by: RITA at September 21, 2006 6:11 AM
hi. im only 16. and tend to worry a lot about having severe problems with myself. and sometimes tend to make things look like i have something wrong with me when i don't. however, since last may i've been having this pressure on the side of my head, like if u were to chew and felt ur temple moving, its like right there. and i didnt know what it was. i went to the doctor and he didnt know. he figured i was stressed out from school or sinuses. mean while, its october and im still having the pressure and still worrying. ive been having headaches all my life. mainly from sinus or allergies, and tylonal takes it away. i havent vommitted, had a seizure or really any of those symtoms. but i just feel extrememly tired and never feel like doing anything besides laying down. should i be worried?
Posted by: danine at October 10, 2006 9:22 PM
I AM A 35 YEAR OLD WOMAN, THAT SEEMS TO BE VERY HEALTHY. I HAVE BEEN TO THE DOCTORS RESENTLY AND HAD ALL BLOOD WORK DONE. I HAD A MAMOGRAM TO CHECK FOR BREAST CANCER AS WELL. ALL TESTE CAME BACK PERFECT. NO BAD BLOOD WORK NO DIABETES , NOTHING. BUT YET FOR THE LAST 6 MONTHS I HAVE FELT VERY LIGHT HEADED AND DIZZY. I GET MINOR HEADACHES AND FEEL A LITTLE DISORIENTED AT TIMES. I ALSO GET NUMBNESS IN MY FINGER TIPS SOME TIMES. I ALSO SEEM TO HAVE SHORT TERM MEMORY LOSS AT TIMES. MY EYES SEM TO BOTHER ME ALOT. IT FEELS KIND OF LIKE THE ROOM IS SPINNING AT TIMES. WHEN I DRINK BEER OR WHEN I AM WORKING OUT I DONT FEEL LIKE THIS. I AM VERY STRESSED MOST OF THE TIME. THE SYMPTOMS SEEM TO BE WORSE DURING THE DAY. DO THESE SOUND LIKE SYMPTOMS OF A BRAIN TUMOR OR CANCER? AND IF YOU HAVE A TUMOR OR CANCER WOULDNT THIS SHOW UP IN YOUR WHITE AND RED BLOOD CELL COUNT?
Posted by: kimberly vick at December 6, 2006 6:42 PM
My girlfriend told me she has a tumor in her head the size of a ping pong ball.Its bulging..i think u can feel it if you touch her scalp.I was wondering if this could be cancer or is it cancer.Or what is it?
Posted by: Lamar at December 10, 2006 6:59 AM
Have been having dizzy spells, feels like im going to pass out. I have to grab hold of something to keep from falling. also i have been having uncontroled muscle tremors, and headaches.
Posted by: kevin at December 31, 2006 4:19 PM
well i have never been color blind till i joined the army i passed my color vision test coming in and now i cant pass it for squat... My optometrist told me today that it is likely that i have a tumor.. i want to know if there is any truth to this because i am very very very worried about what if he is right!! please any info you could give me on the subject would be nice. Thanks
Posted by: michael at January 3, 2007 5:34 PM