Brain Tumor - Types, Signs and Symptoms, Diagnosis, and Treatment

Introduction:

The brain controls activities, such as breathing, walking, the senses (smell, touch, sight), memory, emotions, and personality. When abnormal cells grow and get accumulated in the brain, it is called a brain tumor. These tumors are of various types, some are non-cancerous or benign, and others are cancerous or malignant. The type of tumors that begin in the brain are called primary brain tumors, and the types that spread from other body parts to the brain are called secondary or metastatic brain tumors.

These tumors can occur at any age, and the exact cause is not known still. Exposure to radiation and family history are some of the most common risk factors. Headaches, tingling sensation in the hands and feet, memory problems, and balancing problems, are some of the commonest symptoms of a brain tumor.

Astrocytoma, meningioma, and oligodendroglioma are the most common types of primary brain tumors in adults, and in children, it is medulloblastoma, astrocytoma, and ependymoma. The treatment depends on the stage, location, size, and type of brain tumor. The treatment options are surgery, radiotherapy, and chemotherapy. Palliative care is essential before, during, and after cancer treatment to improve the quality of life by reducing symptoms.

What Are the Types of Brain Tumors?

The types of brain tumors are:

1. Primary Brain Tumors - tumors that originate in the brain tissues.

   1. Glial Brain Tumor - tumor originating in the glial or non-neuronal cells in the brain.

   2. Non-Glial Brain Tumor - a tumor in the nerves, blood vessels, and glands of the brain.

   3. Benign Brain Tumor - a noncancerous brain tumor.

   4. Malignant Brain Tumor - a cancerous tumor in the brain.

2. Secondary or Metastatic Brain Tumors - tumors that arise somewhere else in the body and then spread to the brain.

PRIMARY BRAIN TUMORS:

1. Gangliocytoma - It is a rare type of tumor that originates from mature neurons.

2. Meningiomas - It counts for about 10 to 15 % of all brain tumors, and is the most common benign brain tumor. This tumor arises from the meninges, which are membranes that surround the brain and spinal cord.

3. Craniopharyngiomas - These tumors are difficult to remove because they are located deep in the brain, as they originate in a part of the pituitary gland.

4. Pineocytomas - Tumors that arise from the pineal cells are called pineocytomas. They are usually slow-growing and well-defined.

5. Schwannomas - Primary brain tumors that arise from the Schwann cells, which are cells that assist in nerve impulses, are called schwannomas. Acoustic neuroma, which is a schwannoma arising from the vestibulocochlear nerve (nerve between the brain and the ear), is the most common type.

6. Pituitary Adenomas - These tumors arise from the pituitary gland that is located at the base of the brain. As the pituitary gland regulates most of the hormones produced in the body, the effects of this tumor can be seen in the entire body.

7. Gliomas - This accounts for almost 78 % of all adult malignant brain tumors. These tumors arise from the cells of the brain or spinal cord called the glia. The types of gliomas include:

   1. Ependymomas - When the ependymal cells that line the ventricular system turn cancerous, they give rise to ependymomas.

   2. Glioblastoma Multiforme (GBM) - Also called glioblastoma, and is the most invasive type of glioma. They originate from the star-shaped glial cells like astrocytes and oligodendrocytes. GBM grows rapidly and spreads to other tissues.

   3. Astrocytomas - It is the most common glioma. They develop from astrocytes, which are star-shaped glial cells. They generally occur in the cerebrum.

   4. Brainstem Glioma - Tumors arising in the lowest part of the brain.

   5. Medulloblastomas - It is the most common brain tumor in children and originates in the cerebellum (the lower back part of the brain).

   6. Oligodendrogliomas - These tumors arise from the cells that make myelin (the insulating layer of nerves in the brain and spinal cord).

SECONDARY BRAIN TUMORS:

People with a history of cancer in any part of the body are prone to secondary brain tumors. Secondary brain tumors are more common than primary brain tumors in adults. The common types of cancer that can result in metastatic brain tumor are:

1. Breast cancer.

2. Lung cancer.

3. Melanoma.

4. Colon cancer.

5. Kidney cancer.

Other Tumors That Can Affect the Brain:

1. Atypical Teratoid Rhabdoid Tumors - They are highly invasive and rare tumors that spread throughout the central nervous system. They occur in multiple parts of the body and are common in young children.

2. Hemangioblastomas - These tumors originate from blood vessels.

What Are the Early Signs and Symptoms of a Brain Tumor?

The symptoms depend on the size, type, and location of the tumor. Symptoms usually occur when the tumor presses on a nerve or a part of the brain. The common early signs and symptoms are:

• Severe headaches that typically start in the morning.

• Headaches progressively become severe and frequent.

• Nausea and vomiting.

• Speech problems.

• Changes in vision.

• Hearing difficulties.

• Problems balancing and walking.

• Personality change.

• Mood swings.

• Inability to concentrate.

• Memory problems.

• Twitching.

• Seizures.

• Tingling or numbness in hands or legs.

• Confusion.

There are various other conditions that can result in similar symptoms, so do not panic and consult your doctor for proper diagnosis.

Risk Factors:

1. Radiation exposure.

2. People with a family history of a brain tumor are at risk.

How Does a Doctor Diagnose a Brain Tumor?

To diagnose a brain tumor, the neurologist will first conduct a physical examination and ask you in detail about your symptoms. The doctor will perform a detailed neurological examination, and check if your cranial nerves are intact. He or she might also check your vision, muscle strength, memory, coordination, and balance. In addition, they might ask you to get some of the following tests done:

1. X-rays - To check if the brain tumor has fractured the bones of the skull. They also show calcium deposits that might form in some types of tumors.

2. CT Head - A CT scan of the brain will help the doctor to see the blood vessels and other structures in the brain clearly.

3. MRI Head - MRI of the head provides more detailed pictures of the brain.

4. Angiography - Here, a dye is injected, which travels to the arteries in the brain. This helps the doctor see the blood supply of the tumor.

5. Biopsy - The doctor will collect a small piece from the brain tumor and examine the cells under a microscope. This is done to identify if the tumor is benign or malignant.

What Are the Grades for Brain Tumors?

Your doctor will grade your brain tumor based on how the cells look under a microscope:

1. Grade I - Benign tissue - The cells almost resemble normal brain cells, and they multiply slowly.

2. Grade II - Malignant tissue - The cells resemble normal brain cells less than grade I.

3. Grade III - Malignant tissue - The cells look very different from normal brain cells.

4. Grade IV - Malignant tissue - These cells look abnormal and multiply fast.

Grades I and II are low-grade tumors, and grades III and IV are high-grade tumors. In some cases, a low-grade tumor can turn high-grade with time.

Can a Brain Tumor Be Treated?

The treatment options include:

1) Surgery

If the tumor is well-defined and accessible, the neurosurgeon will try to remove the entire brain tumor. But if the tumor has irregular borders and cannot be separated from the surrounding tissue, or if they are located in a sensitive area of the brain, then surgery is not indicated or the surgeon will try to remove as much tumor as possible, safely.

2) Minimally Invasive Scarless Brain Surgery

Here, brain surgery is carried out through a small incision and specialized instruments, which eliminates the need to cut out large portions of the skull (craniotomy) to gain better access. Getting the tumor removed with this procedure minimizes the risk of serious complications.

3) Chemotherapy

Here, drugs are used to kill tumor cells. These drugs can either be taken orally or get it injected into a vein. Temozolomide is the most common chemotherapeutic drug used for brain tumors.

4) Targeted Drug Therapy

These drugs focus and block a specific abnormality present in the cancer cells. These actions kill cancer cells.

5) Radiation therapy

Here, high-energy beams like X-rays or protons are used to kill tumor cells. There are two types of radiation therapy used:

• External beam radiation - When the radiation used in the therapy comes from a machine placed outside the body.

• Brachytherapy - Here, the source of radiation is placed inside the body and close to the tumor.

Headaches, fatigue, and memory loss are the common side effects of radiation therapy.

6) Radiosurgery

On the contrary to what the name suggests, this is not a type of surgery, but radiosurgery is the use of multiple radiation beams to kill tumor cells in a small area. The kinds of radiosurgery used to treat brain tumors are a Gamma Knife or a linear accelerator.

Rehabilitation:

As brain tumors can affect your motor skills, vision, speech, and thinking, rehabilitation is a must for complete recovery. Depending on your need, the doctor might suggest physical therapy to regain lost motor skills, occupational therapy to go back to a normal routine after brain surgery, and speech therapy to treat difficulty in speaking.

The prognosis of brain tumor will depend on your general health and the size, location, and type of tumor. Early diagnosis and treatment might prevent major complications. So, if you are suffering from symptoms of a brain tumor, make sure you consult a doctor online through phone or video call.