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Brain Tumors
Introduction
Brain tumor is defined as abnormal growth of brain cells (neural or connective cells). They may be malignant (cancerous) or benign (non-cancerous).Suspicion of a brain tumor may first arise from headaches, abnormal behavior or variety of other symptoms. Symptoms would need to be investigated with a series of tests aimed at making a diagnosis. Generally we are able to distinguish between the malignant or benign nature of tumor on the basis of imaging.
Symptoms of Brain Tumors
Symptoms of brain tumors vary widely depending on the type and location of the tumor. However, some of the most common symptoms are headaches, associated with vomiting or nausea. These are often caused by increased intracranial pressure .Besides increase in intracranial pressure; tumors encroach on and/or compress surrounding brain tissue. This would be responsible for the additional symptoms noted by the patients.
| Alarm Signals | Possible Cause to be investigated | |
| first headache complaint from patient over 50 | brain tumor, temporal arteritis | |
| first migraine attack in patient over 40 | brain tumor | |
| headache from patient under 6 | brain tumor, hydrocephalus | |
| Stiffness of the neck/neurological dysfunction | meningitis, brain tumor | |
| headache with signs of elevated ICP | brain tumor | |
| focal neurological dysfunction | brain tumor | |
early morning vomiting or vomiting unrelated to headache or other illness |
brain tumor | |
behavioral changes or rapid decline in school results |
brain tumor | |
| aura migraine always at one side | brain tumor | |
Symptoms associated with the main parts of the brain may include one or more of the following:
Frontal lobe
- Memory loss
- Impaired sense of smell
- Vision loss
- Behavioral, emotional and cognitive changes
- Impaired judgment
Parietal lobe
- Impaired speech
- Inability to write
- Lack of recognition
Occipital lobe
- Vision loss in one or both eyes and seizures
Temporal lobe
- Impaired speech
- Seizures
- Some patients may not exhibit any symptoms
Brainstem
- Irritability
- Difficulty speaking and swallowing
- Drowsiness
- Headache, especially in the morning
- Muscle weakness on one side of the face or body
- Vision loss, drooping eyelid or crossed eyes
- Vomiting
Cerebellum
- increased intracranial pressure (ICP)
- vomiting (usually occurs in the morning without nausea)
- headache
- uncoordinated muscle movements
- problems walking (ataxia)
Diagnosis of the brain tumor is made by:
Neurological examination: This helps us establish the raised intracranial pressure, and focal deficit would help us localise the probable site of tumor.
Magnetic resonance imaging (MRI): MRI is perhaps the most valuable test used to diagnose brain tumors. MRI is useful for diagnosing brain tumors because it provides accurate anatomical location of the tumor, including proximity to important areas (DTI, and functional MRI) probable pathology of the tumor (with the help of spectroscopy/ perfusion studies).
Computed tomography (CT): CT scan may be an alternative. It is less expensive, is good enough for the location of the tumor, but has limitation as compared to MRI study. However it is advantageous in lesion with calcification or bleed in the lesion. Thus on occassions when any of this is suspected we may need CT.
Benign or Malignant?
Benign brain tumors: These are often extra axial in location. Surgery standalone is the treatment for benign tumors.Ofcourse at times due to mere location of the tumor, surgeon may not be able to excise the tumor completely, and then additional radiotherapy or radiosurgery may have to be considered as adjuvent therapy.
Malignant brain tumors: Malignant brain tumors can be slow- or fast-growing and are usually life threatening due to their ability to invade and destroy surrounding normal brain tissue.
There are two types of malignant brain tumors, primary and metastatic.
Primary brain tumors originate from cells in the brain and there are many types of these. The most common type of malignant primary brain tumor is glioblastoma multiforme (grade IV astrocytoma ), which make up approximately 20% of all primary brain tumors.
Metastatic brain tumors are any cancers that have spread from other area of the body to the brain. These tumors are the most common brain tumor,occurring as much as four times more frequently than primary brain tumors. Cancers that commonly spread to the brain include breast and lung cancers.
The prognosis depends on the grade of the malignant tumor, generally gr. 1 ie the pilocytic tumors behave like a benign one,and the patient could be cured of the disease, however they do need long term follow up. The gr 2-4 the lesion would generally recurr. The tumor free period depends on the grade of tumor, and also the response of the lesion to radiation and chemotherapy. In the present era with immunohistology, tumor marker, modern radiotherapy techniques and newer less toxic chemotherapy the outlook of the disease has improved .
Benign or Malignant?
Brain tumors are typically treated with surgery, radiation therapy, chemotherapy, or some combination of these three modalities.
Surgery: Surgery is the primary treatment for brain tumors that can be removed without causing severe damage. Many benign tumors are treated only by surgery but most malignant tumors require treatment in addition to the surgery, such as radiation therapy and/or chemotherapy.
The goals of surgical treatment for brain tumors are multiple and may include one or more of the following:
- Confirm diagnosis by obtaining tissue that is examined under a microscope
- Remove all or as much of the tumor as possible
- Reduce symptoms and improve quality of life by relieving intracranial pressure caused by the tumor
- Provide access for implantation of internal chemotherapy or radiation
A stereotactic / navigation guided biopsy is used to access the tumor in deep seated areas where surgery is hazardous. This technique utilizes a computer and a three-dimensional scan to direct the placement of the needle.
Radiation: Radiation therapy (RT) may be used alone or in combination with surgery and/or chemotherapy in the treatment of primary or metastatic brain tumors.
External Beam RT is the conventional technique for administering radiation therapy for brain tumors.
The CyberKnife is a frameless robotic radiosurgery system used for treating benign tumors, malignant tumors and other medical conditions. The CyberKnife system is a method of delivering radiotherapy, with the intention of targeting treatment more accurately than standard radiotherapy. This System improves on other radiosurgery techniques by eliminating the need for stereotactic frames. As a result, the CyberKnife System enables doctors to achieve a high level of accuracy in a non-invasive manner and allows patients to be treated on an outpatient basis. The CyberKnife System can pinpoint a tumor's exact location in real time using X-ray images taken during the brain cancer treatment that reference the unique bony structures of a patient's head.The CyberKnife System has a strong record of proven clinical effectiveness. It is used either on a stand–alone basis or in combination with other brain cancer treatments, such as chemotherapy, surgery or whole brain radiation therapy.
Chemotherapy: Treating brain tumors with chemotherapy is more complicated than treating tumors elsewhere in the body because of a natural defense system called the blood-brain barrier that protects the brain from foreign substances.Furthermore, not all brain tumors are sensitive to or respond to chemotherapy, even if the drug does penetrates the bloodbrain barrier. Actively dividing cells are the most vulnerable to chemotherapy. Most tumor cells and some normal cells fall into that category.
Other Supportive Treatments:
Dexamethasone (synthetic steroid - To control cerebral edema or accumulation of fluid
Urea and mannitol (diuretic) - To reduce brain swelling
Analgesics or pain killers - To reduce pain
Antacids - To reduce stress ulcers
Phenytoin (anticonvulsant) - To reduce seizures
Rehabilitation (to regain lost motor skills and muscle strength; speech, physical, and occupational therapists may be involved in the healthcare team)
Continuous follow-up care (to manage disease, detect recurrence of the tumor, and to manage late effects of treatment)
Newer therapies that may be used to treat brain cancer include the following:
- Chemotherapy wafers - wafers containing a cancer-killing drug, BCNU, are inserted directly into the area of the brain tumor during surgery.
- Immumotherapy is under research and in future may change the way we treat brain tumors.
PROSTATE CANCER
What is the prostate gland?
The prostate gland is a male sex gland. It produces a thick fluid that forms the majority part of the semen. The normal prostate in a young male has is a walnut-sized gland, and a normal prostate gland measures approximately 20 cc. The average prostate in a patient with prostate cancer is approximately 40 cc in size. The prostate gland is located below the urinary bladder and in front of the rectum. The prostate surrounds the upper part of the urethra, the tube that empties urine from the bladder. ?The prostate needs male hormone to function. The main male hormone is testosterone, which is made mainly by the testicles. Approximately 10% of male hormones are produced in small amounts by the adrenal glands, which are located about our kidneys.
What is prostate cancer?
Prostate cancer develops from the growth of cancerous cells within the prostate gland and probably it is 4th commonest in India. Although the cause of prostate cancer is still unknown, it might be associated with increased testosterone level, a family history of prostate cancer, high fat diet, and age. Commonly diagnosed benign prostatic hypertrophy (BPH) does not increase the risk of developing prostate cancer, according to most clinical studies. Prostate cancers are relatively rare in young patients. The risk for prostate cancer increases significantly with age. Almost all prostate cancers are adenocarcinomas. Other types of cancer, such as transitional squamous, cell carcinomas, and small cell cancers are very rare. The incidence of prostate cancer has rose continuously for more than two decades. The rise in incidence is partially caused by improved detection capability, especially using prostate-specific antigen (PSA) blood test. Prostate cancer tends to arise from the peripheral zone of the prostate. Patients are often asymptomatic at diagnosis. Early onset of obstructive urinary symptoms are not very common due to the location of most prostate cancers. At the time of diagnosis, the cancer can remain in the prostate gland (localized) or spread (metastasize) to nearby lymph nodes, bladder, rectum or more remote organs such as bone and liver. Bone is the most common site of prostate cancer metastases.
What are the symptoms of prostate cancer?
Prostate cancers usually do not have any symptoms in the early stages. Early cases are either diagnosed because the physician performs a digital rectal exam (DRE) and feels an abnormality in the gland, or because the PSA blood test is used to screen for the cancer. The presence of symptoms usually indicates advanced disease. Advanced prostate cancers can lead to many symptoms such as weakness in urinary stream, difficulty in initiation of urination, difficulty with emptying the bladder completely, a burning sensation with urination, blood in the urine, weight loss, or bone pain. However, these symptoms are NOT specific for cancer and in fact are much more commonly associated with other prostate and bladder conditions such benign prostatic hyperplasia (BPH) or bladder infection. The most common site for prostate cancer to spread is to bones. Pain in the lower back, ribs, pelvis, and other bony structure are the most common presenting symptom in patients with bony metastases. When the patient has metastatic disease to the spine, symptoms of spinal cord compression may develop. Common symptoms found in spinal cord compression include pain, urinary incontinence, paraplegia, and paralysis. Spine cord compression is a medical emergency and may cause permanent paralysis if not treated appropriately within a limited amount of time.
How is prostate cancer diagnosed?
Before the discovery of prostate specific antigen (PSA), prostate cancer is usually diagnosed by physical examination. Physical examination (digital rectal examination) typically reveals an induration or nodularity of the prostate. Nodules of the prostate cancer are generally hard and painless. Patients with advanced prostate cancer may also present with bony pain (from bony metastases) and/or inguinal lymph adenopathy. PSA is a protein that serves as a tumor marker unique to the prostate gland. PSA test significantly increases the yield of digital rectal examination in the diagnosis of prostate cancer. PSA blood test can detect prostate cancer of very low volume and is used in initial diagnosis and diagnosis of recurrent disease after treatment. PSA is relatively sensitive and specific for the screening of prostate cancer, but it should be used with physical examination and other imaging studies, such as transrectal ultrasound (TRUS), for the diagnosis of the disease. The standard method to diagnose prostate cancer is a true-cut prostate biopsy after a positive serum PSA test or DRE. A bone scan is very sensitive for detecting bony metastases from prostate cancer in patients with high serum PSA level or bony pain. CT scans and MRI are used to evaluate the extent of prostate cancer in the pelvis. They are usually used to detect the lymph adenopathy in the pelvis and low abdomen.
How is prostate cancer staged?
If cancer is found in the prostate, your physicians need to know the stage, or extent, of the disease. Staging is a careful attempt to find out whether the cancer has spread and, if so, what parts of the body are affected. The doctor may use various blood and imaging tests to learn the stage of the disease. Treatment decisions depend on these findings. The results of staging tests help the doctor decide which stage best describes a patient's disease. Clinical and pathological stage of the disease is one of the most important prognostic factors for patient's survival.
Who is at risk for developing prostate cancer?
The cause of prostate cancer is unknown at this time. Many factors increase the likelihood of developing prostate cancer.
Age. Prostate cancer is uncommon in patients under 50 years old. More than 80% of all prostate cancer patients are older than 65. It is known that the chance of developing prostate cancer is higher in males older age of 50. It is recommended that these individuals undergo annual PSA screening test and Digital Rectal Exam.
Family History. Prostate cancer may have a genetic link. Human gene related to the disease has not been discovered, however. Male patients with positive family history of prostate cancer in the father or brother have much higher risk (two to seven fold increase) of developing prostate cancer. The risk gets even higher if several relatives have been affected, especially if they were young at the time of diagnosis.
Benign Prostatic Hypertrophy (BPH). Many elderly males are diagnosed with BPH. Studies have shown that BPH is not related to higher risk of developing prostate cancer. However, patients with BPH is recommended to have annual PSA test and Digital Rectal Exam for screening purposes.
Diet. High fat diet may increase the risk of developing prostate cancer. Recent studies have shown that a diet high in lycopenes (found in higher levels in fruits and vegetables), Turmeric (curcumin), Vitamin E, and selenium may lower the risk of developing prostate cancer.
How is prostate cancer treated?
Treatment depends on the stage at which the cancer is found and on the age and health status of the patient. Surgery and radiation therapy are options for cancer that is confined to the prostate. Standard treatment involves either removal of the entire prostate gland (radical prostatectomy) or radiation therapy aimed at the pelvic area.
Shall I receive hormone therapy?
Hormone therapy prevents the prostate cancer cells from getting the male hormones they need to grow. When a man undergoes hormone therapy, the level of male hormones is decreased. This drop in hormone level can affect all prostate cancer cells, even if they have spread to other parts of the body. For this reason, hormone therapy is called systemic therapy. Not every patient diagnosed with prostate cancer needs hormonal therapy. Hormonal therapy is usually used prior to surgery or radiotherapy to reduce the volume of the prostate gland. This procedure is called cytoreduction. Patients with poorly differentiated disease, locally advanced disease, and severely enlarged prostate gland should receive hormonal treatment before their definitive therapy. Prostate cancer that has metastasized to other parts of the body usually can be controlled with hormone therapy for a period of time.
