Brain Tumor: Causes, Symptoms, Types & Tests

A brain tumor is abnormal cell growth in and around the brain. Brain tumors are non-cancerous (benign) or cancerous (malignant). Unfortunately, they also begin in the brain (primary) or occur because cancer has spread to the brain from another location (secondary/metastatic). Brain tumor symptoms and side effects also differ depending on the brain tumor location, size, and type. Other health conditions also cause some of these symptoms, so although someone has a headache or another neurological symptom, it does not mean that they have a brain tumour. It is important to evaluate the patient medically, especially if symptoms persist, are unusual, or are worsening.

What Is a Brain Tumor?

A brain tumour consists of an abnormal mass of tissue that develops in or on the brain. A tumour invades healthy brain tissue adjacent to the tumour, swells, or exerts pressure within the skull. Brain tumors are tumours are either benign or malignant. Although benign tumors do not have cancer cells in them, when they press on an important brain area, they cause problems. Malignant tumors may grow faster and invade neighbouring tissues. Brain tumors are also classified based on the position in which they are located and the cells and/or tissue in which they originate. Some tumors start out in the brain, and others in other parts of the body migrate to the brain.

Brain Tumor Causes

Although we know much more about the causes of most brain tumors, we do not yet know the exact cause. Some tumours appear to be caused by genetic and environmental factors. A few genetic disorders passed down in families make it more likely that brain and central nervous system tumors form. Radiation therapy, especially during childhood, and other chemotherapy treatments also have been associated with a small number of brain tumors. 

Most people with a brain tumor, however, have no specific cause. Also keep in mind that most symptoms, such as headaches that occur in the day-to-day life of a healthy child, are not related to a brain tumor. Additional tests are recommended by a doctor if there are signs or symptoms that an imaging test or other evaluation is required.

Brain Tumor Symptoms

The signs and symptoms of brain tumors vary from one person to another. This is due in part to the fact that there are distinct parts of the brain that control distinct functions. The symptoms thus vary depending on the size and location of a tumor. Typical symptoms of a brain tumour include headaches that don't go away or are unusual, nausea, vomiting, seizures, changing vision or hearing, problems with memory and changes in personality or behaviour. 

Other symptoms include difficulty with concentration, balance, walking, speech or movement. If a person has just a headache, that doesn't necessarily indicate a brain tumor. If headaches are new, occurring more often, or becoming worse, however, seeking medical advice is recommended if the headaches are accompanied by other symptoms such as seizures, weakness, vision changes, confusion, or problems with balance.

Types of Brain Tumors

There are many different brain tumor types. They are categorized by the cells or tissues that they form from; by where they grow and whether they are benign (harmless) or malignant (cancer). Gliomas, meningiomas, and pituitary tumors are among the most frequently mentioned types of brain tumors. Others include schwannomas and ependymal tumors. There are several types (subtypes) of gliomas, including astrocytic tumors and oligodendroglial tumors.

Brain tumors are also said to be primary or metastatic. Primary brain tumors are those that develop in brain tissue or the tissues surrounding the brain, while metastatic brain tumors develop when cancer that started in other parts of the body moves to the brain. Some tumours are given a grade that is based on the rate at which their cells grow and on microscopic and molecular features. This helps physicians to better understand the tumor and provide proper treatment.

Brain Tumor Tests

If a brain tumor is suspected, a physical examination, a neurological examination, and a medical history start the examination. Neurological tests evaluate functions like coordination, movement, reflexes, balance, hearing, and vision. Imaging plays an important role in the evaluation of brain tumors. The physician suggests an MRI or CT scan, depending on the clinical findings and symptoms.

Brain MRI for Tumor Detection

A brain MRI uses a strong magnetic field, radio waves, and a computer to produce detailed images of the brain. MRI is an important test for suspected brain tumors because it does not involve ionizing radiation and gives detailed images of all soft tissues. Brain MRI is carried out with or without contrast, depending on what the doctor wants to assess. Imaging also shows extra details of an abnormal smell and its surrounding structures. MRI also tracks a brain tumor over time to measure changes in the tumor when being treated and to determine the outcome of treatment.

Conclusion

Brain tumors are not always malignant and occur in various locations of the brain. Symptoms are dependent on the size, location, and type of tumor. Symptoms vary from person to person: headaches, seizures, nausea, vomiting, vision changes, hearing impairment, memory loss, and behaviour irregularities. If a brain tumor is suspected, further tests are ordered, including neurological exams, an MRI, and a CT scan (possibly other tests, depending on the individual). 

Sometimes further tests or a biopsy are required to identify what an abnormality is in some cases.

In case of any neurotypical symptoms, whether they are persistent or not, please don't make your own diagnosis, but consult someone else whom you know and trust to answer your questions. Support such as evaluation and imaging are used to uncover the underlying cause, if the cause is to be determined, and to plan the next steps.