Brain Tumor, Brain Surgery & Neuro Oncology

If someone has a brain tumor, it does not always mean they will need surgery. A brain tumor is an abnormal mass of cells in or around the brain. The skull, which encloses the brain, is very rigid. Any growth inside such a restricted space can cause problems.

Brain tumors can be diagnosed as malignant (cancerous) or benign (noncancerous). Some tumors grow quickly, while others are slow growing and only about one-third of brain tumors are actually cancerous. But whether they’re cancerous or not, brain tumors can compromise brain function and your health if they grow large enough to press on surrounding nerves, blood vessels, and tissue. Tumors that develop in your brain are called primary tumors. Tumors that spread to your brain after forming in a different part of your body are called secondary tumors, or metastatic brain tumors. There are many different types of Tumors and many ways to treat them.

A brain tumor, known as an intracranial tumor, is an abnormal mass of tissue in which cells grow and multiply uncontrollably, seemingly unchecked by the mechanisms that control normal cells. More than 150 different brain tumors have been identified, but the two main brain tumors are categorised as primary and metastatic.

Primary brain tumors originate from the brain’s tissues or the brain’s immediate surroundings. Primary tumors are categorised as glial (made up of glial cells), non-glial (developed on or in the brain’s structures and nerves, blood vessels and glands), and malignant or benign.

Types of brain tumors

• Chordomas are benign, slow-growing tumors that are most prevalent in people ages 50 to 60. The most common location for a tumor is the skull’s base and the spine’s lower portion. Although these tumors are benign, they may invade the adjacent bone and pressure nearby neural tissue. These are rare tumors, contributing to only 0.2 percent of all primary brain tumors.

• Craniopharyngiomas are typically benign but are more difficult to remove because of their location near critical structures deep in the brain. They usually arise from a portion of the pituitary gland (the structure that regulates hormones in the body), so nearly all patients will need some hormone replacement therapy.

• Gangliocytomas, gangliomas and anaplastic gangliogliomasare rare tumors that include neoplastic nerve cells that are relatively well-differentiated, occurring primarily in young adults.

• Glomus jugulare tumors are most frequently benign and typically are located at the top of the jugular vein and just under the skull base. They are the most common form of glomus tumor. However, glomus tumors generally contribute to less than 1% per cent of head and neck neoplasms.

• Meningiomas are the most common benign intracranial tumors, comprising 10-15% of all brain neoplasms, although a very small percentage are malignant. These tumors originate from the meninges, the membrane-like structures surrounding the brain and spinal cord.

• Pineocytomas are generally benign lesions that arise from the pineal cells, occurring predominantly in adults. They are most often well-defined, noninvasive, homogeneous, and slow-growing.

• Pituitary adenomas are the most common intracranial tumors after gliomas, meningiomas and schwannomas. The large majority of pituitary adenomas are benign and relatively slow-growing. Even malignant pituitary tumors rarely spread to other parts of the body. Adenomas are by far the most common disease affecting the pituitary. They commonly affect people in their 30s or 40s, although they are also diagnosed in children. Most of these tumors can be treated successfully.

• Schwannomas are common benign brain tumors in adults. They arise along nerves, comprised of cells that generally provide the “electrical insulation” for the nerve cells. Schwannomas often displace the remainder of the normal nerve instead of invading it. 

• Acoustic neuromas are the most common schwannoma, arising from the eighth cranial nerve, or vestibular cochlear nerve, which travels from the brain to the ear. Although these tumors are benign, they can cause severe complications and even death if they grow and exert pressure on nerves and eventually on the brain. Other locations include the spine and, more rarely, along nerves that go to the limbs.

• Gliomas are the most prevalent type of adult brain tumor, accounting for 78 percent of malignant brain tumors. They arise from the supporting cells of the brain, called the glia. These cells are subdivided into astrocytes, ependymal cells and oligodendroglial cells (or oligos). Glial tumors include the following:

• Astrocytomas are the most common glioma, accounting for about half of all primary brain and spinal cord tumors. Astrocytomas develop from star-shaped glial cells called astrocytes, part of the brain’s supportive tissue. They may occur in many areas of the brain, but most commonly in the cerebrum. People of all ages can develop astrocytomas, but they are more prevalent in adults — mainly middle-aged men. Astrocytomas in the base of the brain are more prevalent in children or younger people and account for most pediatric brain tumors. In children, most of these tumors are considered low-grade, while in adults, most are high-grade.

• Ependymomas are derived from a neoplastic transformation of the ependymal cells lining the ventricular system and account for 2-3% of all brain tumors. Most are well-defined, but some are not.

• Glioblastoma multiforme (GBM)is the most invasive type of glial tumor. These tumors tend to grow rapidly, spread to other tissue and have a poor prognosis. They may be composed of several different kinds of cells, such as astrocytes and oligodendrocytes. GBM is more common in people ages 50 to 70 and is more prevalent in men than women.

• Medulloblastomas usually arise in the cerebellum, most frequently in children. They are high-grade tumors but are usually responsive to radiation and Chemotherapy.

• Oligodendrogliomas are derived from the cells that make myelin, which is the insulation for the brain’s wiring.

Metastatic Brain Tumors

Metastatic brain tumors include tumors that arise elsewhere in the body (such as the breast or lungs) that migrate to the brain, usually via the bloodstream. Metastatic tumors are considered cancer and are malignant. Historically, the outcome for patients diagnosed with metastatic tumors was very poor, with typical survival rates of just several weeks. More sophisticated diagnostic tools, combined with new surgical innovation and radiation approaches, have helped survival rates extend years, providing an improved quality of life for patients following diagnosis.

Other Types of Brain Tumors

Hemangioblastomas originate from blood vessels. They are slow-growing tumors commonly located in the cerebellum. They are often accompanied by a cyst and can be significant in size. These tumors are most common in people ages 40 to 60 and more prevalent in men than women.

Rhabdoid tumors are highly aggressive and rare tumors that tend to spread throughout the central nervous system. They often appear in multiple sites in the body, especially in the kidneys. They are more prevalent in young children but also can occur in adults.

Brain Tumor Symptoms

The symptoms of brain tumors depend naturally by the type of tumor and the grade of the Tumor, the magnitude and the position of the mass. Large parts of the brain can be involved in some diseases, and there may be relatively few symptoms. Alternatively, very tiny lesions may be catastrophic if they occur in a critical part of the brain.

Two categories of brain tumor symptoms can be broadly distinguished:

1. General Brain Tumor: those caused by the pressure exerted by the tumor mass on the brain or on the CSF transit routes (general symptoms of the brain Tumor: headache, mental slowdown, mood changes, nausea and vomiting) or seizures, which are symptom of the onset of brain tumors (for this reason, if a person experiences a seizure in adulthood they should always undergo a brain MRI)

2. Specific Brain Tumor: those produced by the site where the tumor is located that causes the interruption or slowdown of one or more brain functions that selectively lead to different deficits

10 Early Warning Signs and Symptoms of a Brain Tumor

Initial signs and symptoms of a brain lesion are often non-specific and may include:

1. headache (which tends to get worse in the morning and with activities)
2. Nausea
3. Fever (if an infection is present)
4. Neck pain and stiffness (if the meninges are inflamed)
5. Visual impairment,
6. Speech problems, and difficulty forming words
7. Weakness or paralysis to one side of the body
8. loss of strength in a limb or half of the body (hemisome)
9. Seizures
10. Personality changes, loss of concentration, aggression or loss of personal control

Brain Tumor Symptoms Based on Their Location

Depending on the lobe where the mass was formed, it is possible to distinguish some initial symptoms :

• Tumor in the frontal lobe – symptoms such as weakness, confusion, mood changes, extreme difficulty or complete inability to move a specific body part, speech disorders (dysphasia, aphasia …)

• Tumor in the parietal lobe – symptoms such as inability to manage particular  actions and movements (e.g. holding cutlery, writing), lack of strength, paresis or paralysis disturbances in the understanding of language

• Tumor in the occipital lobe – symptoms such as partial or complete visual disturbances (up to blindness),

• Tumor in the temporal lobe – symptoms such as dizziness and in general, disorders related to balance and spatial perception, inability to express oneself verbally, inability to understand and perform elementary actions, language disorders

Brain Tumors can also lead to intracranial hypertension. Symptoms of chronic intracranial hypertension (IH) can include:

• a constant throbbing headache which may be worse in the morning or when coughing or straining; it may improve when standing up
• temporary loss of vision – the vision may become dark or “greyed out” for a few seconds at a time; this can be triggered by coughing, sneezing or bending down
• feeling and being sick
• feeling sleepy
• feeling irritable

Chronic intracranial hypertension can sometimes result in permanent vision loss, although treatment can help to reduce the chances of this happening.

Brain Tumor Causes and Risk Factors

Tumors are formed from pathological cells. These cell anomalies are due to an error that leads to a genetic mutation of the cells themselves, so they begin to grow and multiply faster than the natural rate that affects healthy cells.

As with many other tumors, the causes of brain tumors are not easy to identify. However, it is possible to isolate what are believed to be the major risk factors for a brain tumor, and  increases the possibility of developing an oncological pathology linked to the central nervous system:

Advanced age: although some types of brain tumors mainly affect children and adolescents (e.g. medulloblastoma), most cancers affect adults and the elderly (with a peak between 60 and 80 years)

Exposure to carcinogens such as some fertilizers and pesticides, but also vinyl chloride

Exposure to high-dose ionising radiation – (e.g. X-ray radiation) is among the main risk factors of glial-type brain tumors. It has been shown that the disease can occur even many years after exposure

Genetic predisposition – Brain tumors are not inherited per se, however, in some cases, there may be a hereditary disease associated with the formation of genetically transmitted intracranial tumors within a family. For this reason, in the broad sense, the brain tumor that occurs during type 1 and 2 neurofibromatosis; Turcot’s syndrome; Li Fraumeni syndrome; Cowden syndrome and Von Hippel Lindau syndrome can be considered hereditary.

Use of mobile phones: there is no certainty about it, however, it is advisable to minimize the use of these devices, especially in children and young people

Weakening of the immune defenses: a typical case is that of AIDS patients. Decreased immune defenses are one of the most serious risk factors for primary brain cancer, particularly lymphoma.

The causes and risk factors that lead to the formation of brain tumors (including eating habits and lifestyle), are not demonstrable despite many studies. To date, it is not possible to scientifically support the usefulness of any preventive strategy.

Brain Tumor Diagnosis & Investigation

The process brain tumor diagnosis is initiated when the initial symptoms of the disease are present.

Generally, the identification of brain tumor symptoms alerts the patient himself, his family or a general practitioner (GP). The appropriate course of action is to proceed with booking a neurosurgical visit, where a full neurological examination will be undertaken. 

A neurological exam may include, among other things, checking the vision, hearing, balance, memory, motility, sensitivities, cranial nerve functions, coordination, strength and reflexes. Difficulty in one or more areas may provide clues about the part of the brain that could be affected by a brain tumor.

If it’s suspected that the patient had a brain tumor, the Neurosurgeon may recommend radiological investigation (imaging tests) or other diagnostic procedures, which may include:

• Functional MRI is used to simultaneously detect the various cortical areas’ activation while performing specific actions. This exam allows the neurosurgeon to understand how close the Tumor is to an important area.

• MRI with spectroscopy is a necessary investigation to evaluate, highlighting the peaks of acetylcholine and nicetyl-aspartate in the Tumor, the grading of malignancy of the same

• AngioRM is particularly useful in the case of vascular tumors such as angiomas or particularly vascular Tumors such as hemangioblastomas, hemangiopericytomas, malignant or anaplastic meningiomas or to study the satellite veins of cerebral cavernomas or as a pre-surgical study for the visualisation of venous sinuses

• When the patient is unable to perform the MRI, for example – a pacemaker wearer, but also in the case of any emergencies due to intracranial hypertension syndrome, a CT with contrast medium will be carried out to detect the brain tumor.

• Computed Tomography (CT)is very important in oncology, less useful in MRI brain oncology. The total body CT Scan allows to obtain, through sequential images, a precise and detailed picture of the internal organs and is used in brain metastases to search for the primary Tumor. Although the CT Scan is sometimes used as a screening test for a brain tumor. An iodinated contrast medium allows the doctor to obtain more defined images of any Tumor mass.

• Tests to find cancer in other parts of the body.If it’s suspected that the brain tumor may result from cancer that has spread from another area of the body, the doctor may recommend tests and procedures to determine where the cancer originated. One example might be a CT or PET scan to look for signs of lung cancer.

• Collecting and testing a sample of abnormal tissue (biopsy).A biopsy can be performed as part of an operation to remove the brain tumor, or a biopsy can be performed using a needle.

• A stereotactic needle biopsy may be done for brain tumors in hard-to-reach areas or very sensitive areas within the brain that might be damaged by a more extensive operation. The neurosurgeon drills a small hole into the skull. A thin needle is then inserted through the hole. Tissue is removed using the needle, which is frequently guided by CT or MRI scanning.

The biopsy sample is then viewed under a microscope to determine if it is cancerous or benign. Sophisticated laboratory tests can give the doctor clues about the prognosis and treatment options.

Following a detailed investigation, it may be necessary to proceed with a neurosurgical intervention. More rarely, if the tumor is to be considered inoperable, at the biopsy and the subsequent assessment and diagnosis of the results by the neurosurgeon. The detailed ultrastructural study under the microscope of any sample taken will identify the atypical cells and will establish, consequently, how to intervene and what will be the most suitable complementary treatments to surgery for the treatment of that specific tumor.

Brain Tumor Treatments

To select the most suitable therapy for the treatment of brain Tumor it is necessary to evaluate a number of factors, such as:

• the typology : primitive, astrocytoma, glioblastoma (malignant); meningioma, neuroma (benign); secondary, otherwise called metastatic, with the location of the organ where the tumor originated
• the site of the brain tumor: subcortical cortex, brain center, lobar, anterior middle or posterior cranial fossa
• its nature (malignant or benign brain tumor) with a grading of malignancy from I-IV
• the neurological status of the patient
• his/her general clinical condition.

Depending on the results resulting from the previous evaluation, the neurosurgeon will proceed with:

A Neurosurgical Intervention

Radiosurgery

Radiotherapy,  

Chemotherapy

Targeted Drug Therapy

Rehabilitation After Treatment

In treating brain tumors, the various methods are administered separately or in combination with each other, depending on the specific cases.

Neurosurgical Intervention

Surgery is commonly the treatment of choice for a brain tumor. Surgery makes it possible to clearly define the histological diagnosis, remove the mass and reduce the increase in intracranial pressure caused by the brain tumor (among the initial symptoms, certainly one of the most important), all to significantly improve the quality of life of a patient.

If the brain tumor is located in a place that is accessible for an operation, the surgeon will take a surgical approach to remove as much of the brain tumor as possible. In some cases, tumors are small and easy to separate from surrounding brain tissue, which makes complete surgical removal possible. In other cases, tumors can’t be separated from surrounding tissue or they’re located near sensitive areas in the brain, making surgery risky. In these situations, the doctor removes as much of the tumor as is safe. Even removing a portion of the brain tumor may help reduce the signs and symptoms.

Surgery to remove a brain tumor carries risks, such as infection and bleeding. Other risks may depend on the part of the brain where the tumor is located. For instance, surgery on a tumor near nerves that connect to the eyes may carry a risk of vision loss.

Craniotomy: Brain neurosurgery operations consist of craniotomy (usually under general anaesthesia), i.e. opening the skull and removing the tumor. However, it is not always possible to altogether remove the mass, and sometimes, surgery is not feasible. Surgery is not proposed for patients who have a brain tumor localised to a site that has involved structures that are functionally essential for life, such as the bulb, pons, midbrain or basal nuclei, or when the spread of the Tumor is too advanced having involved more cerebral lobes, or when the general and neurological conditions of the patient do not allow surgical manoeuvres.

Awake Craniotomy: Today, even the types of brain tumors located in critical areas can be removed, thanks to the development of the awake surgery technique. These innovative brain neurosurgery interventions allow the operation of awake patients and consequently allow the active monitoring of movement and speech functions to preserve them and allow maximum Tumor removal. This procedure is offered at very few medical centres in the country and is used to help certain people who’ve been told they have an inoperable brain tumor. Using this procedure, the neurosurgeon is able to remove the tumor safely with minimised risk of serious complications.

In other patients, techniques involving surface or depth electrode monitoring may sometimes be used to monitor functions such as motility, sight, the state of the cranial nerves (responsible for speech, swallowing, ocular motility, sight, facial sensitivity, facial motility, etc.) and significantly reduce the incidence of complications.

Minimally invasive techniques. People who undergo brain tumor surgery with these advanced approaches often experience reduced hospital stays, shorter recovery times and a lower expected mortality rate. Many people who undergo brain tumor surgery leave the hospital in one or two days. Neurosurgeons are able to do these precise and complicated surgeries because they work with specialists in brain imaging (neuroradiologists) and use advanced surgical navigation and mapping equipment. They are able to visualise exactly where the tumor is and the surgical path to it.

Radiosurgery Stereotactic radiosurgery is not a form of surgery in the traditional sense. Instead, radiosurgery uses multiple beams of radiation to give a highly focused form of radiation treatment to kill the tumor cells in a very small area. Each beam of radiation isn’t particularly powerful, but the point where all the beams meet — at the brain tumor — receives a very large dose of radiation to kill the tumor cells.

Radiosurgery is typically done in one treatment, and in most cases, the patient can go home the same day.There are different types of technology used in radiosurgery to deliver radiation to treat brain tumors, such as a Gamma Knife or linear accelerator. 

Radiation Therapy uses high-energy beams, such as X-rays or protons, to kill tumor cells. Radiation therapy can come from a machine outside the body (external beam radiation). In rare cases, radiation can be placed inside the body close to the brain tumor (brachytherapy).

External beam radiation can focus just on the area of the brain where the tumor is located, or it can be applied to the entire brain (whole-brain radiation). Whole-brain radiation is most often used to treat cancer that spreads to the brain from some other part of the body and forms multiple tumors in the brain.

A newer form of radiation therapy using proton beams is being studied for use in people with brain tumors. For tumors that are very close to sensitive areas of the brain, proton therapy may reduce the risk of side effects associated with radiation. But proton therapy hasn’t proved to be more effective than standard radiation therapy with X-rays.

Side effects of radiation therapy depend on the type and dose of radiation the patient receives. Common side effects during or immediately following radiation include fatigue, headaches, memory loss and scalp irritation.

Chemotherapy uses drugs to kill tumor cells. Chemotherapy drugs can be taken orally in pill form or injected into a vein (intravenously). The chemotherapy drug used most often to treat brain tumors is temozolomide (Temodar), which is taken as a pill. Many other chemotherapy drugs are available and may be used depending on the type of cancer.

Chemotherapy side effects depend on the type and dose of drugs the patient receives. Chemotherapy can cause nausea, vomiting, and hair loss. Tests of the brain tumor cells can determine whether chemotherapy will be suitable for the patient. Depending in the type of brain tumor diagnosed will also help determine whether to recommend chemotherapy.

Targeted drug therapy focuses on specific abnormalities present within cancer cells. By blocking these abnormalities, targeted drug treatments can cause cancer cells to die. Targeted therapy drugs are available for certain types of brain tumors, and many more are being studied in clinical trials. Many different forms of targeted therapy are being developed.

Rehabilitation after treatment

Because brain tumors can develop in parts of the brain that control motor skills, speech, vision, and thinking, rehabilitation may be a necessary part of recovery. Depending on the needs, the doctor may refer the patient to:

• Physical therapy to help the patient regain lost motor skills or muscle strength
• Occupational therapy to help the patient get back to normal daily activities, including work, after a brain tumor or other illness
• Speech therapy with specialists in speech difficulties (speech pathologists) to help if the patient is having difficulty speaking.