Skip to Content

What happens if a brain tumor is left untreated?

Brain tumors are abnormal growths of cells within the brain. They can occur in people of all ages and can be classified into various types based on their origin and characteristics. While early detection and treatment are crucial for managing brain tumors effectively, the consequences of leaving them untreated can be severe. In this blog post, we will explore what happens if a brain tumor is left untreated, including the potential complications and risks involved.

Types of Brain Tumors

Before delving into the consequences of untreated brain tumors, it is important to understand the different types of brain tumors. The most common category of brain tumors is gliomas, which originate from the glue-like supportive cells of the brain. Within gliomas, there are several subtypes, including astrocytomas, oligodendrogliomas, and ependymomas.

Apart from gliomas, there are also non-gliomas, which originate from other types of brain cells. This category includes meningiomas, which arise from the meninges (protective membranes covering the brain), pituitary tumors that develop in the pituitary gland, and medulloblastomas, which occur primarily in children.

Potential Consequences of Leaving a Brain Tumor Untreated

If left untreated, brain tumors can have various consequences on the affected individual. These consequences can range from the growth and progression of the tumor to damage to surrounding brain structures, impaired cognitive function, worsening symptoms and quality of life, and an increased risk of seizures. Let’s explore each of these consequences in more detail.

Tumor Growth

One significant consequence of leaving a brain tumor untreated is the continued growth and expansion of the tumor mass. As the tumor grows, it can start to press on and compress surrounding brain tissue. This compression and displacement of brain tissue can lead to an increase in intracranial pressure, which can be harmful to the brain’s function and overall well-being.

Damage to Surrounding Brain Structures

The growth of a brain tumor can also result in damage to surrounding brain structures. Depending on the location of the tumor, this can impair vital functions controlled by specific regions of the brain. For example, a tumor in the motor cortex can lead to muscle weakness or paralysis, while a tumor in the language centers can cause difficulties with speech and language ability.

Additionally, the presence of a tumor can disrupt normal brain activity and communication between different regions, further contributing to neurological deficits.

Impaired Cognitive Function

Brain tumors can also have a significant impact on cognitive function. As they grow and affect different areas of the brain, they can impair cognitive processes such as memory, concentration, problem-solving, and reasoning. Memory loss is a common cognitive impairment associated with brain tumors, and individuals may experience difficulties with both short-term and long-term memory.

Furthermore, brain tumors can affect language processing, leading to difficulties with speech, reading, writing, and understanding complex information. These cognitive impairments can significantly impact an individual’s daily functioning and quality of life.

Worsening Symptoms and Quality of Life

Leaving a brain tumor untreated can lead to a progressive worsening of symptoms and a decline in the overall quality of life. As the tumor grows and exerts more pressure on surrounding structures, individuals may experience increased pain and discomfort.

The presence of a tumor can also affect mobility and coordination, resulting in difficulties with walking, balance, and fine motor skills. These physical limitations can further impact an individual’s independence and ability to carry out everyday tasks.

Additionally, untreated brain tumors can cause psychological and emotional distress. The uncertainty and fear surrounding the condition, along with the physical symptoms and limitations, can lead to anxiety, depression, and other mental health challenges.

Potential Risk of Seizures

Another consequence of leaving a brain tumor untreated is an increased risk of seizures. Brain tumors can disrupt the normal electrical activity of the brain, leading to abnormal electrical discharges that result in seizures. These seizures can vary in severity and frequency, and they may cause impaired motor function, loss of consciousness, and a risk of injury during seizure activity.

The risk of seizures can have a significant impact on an individual’s daily life and may require ongoing management and treatment to control and reduce their occurrence.

Potential Complications

Apart from the immediate consequences of leaving a brain tumor untreated, there are also potential complications that can arise over time. These complications include tumor progression, neurological deficits, and increased risks during treatment.

Tumor Progression

If a brain tumor is left untreated, there is a higher risk of tumor progression. This means that the tumor can grow in size and invade surrounding tissues, potentially leading to metastasis (spread) to other parts of the brain or even to distant organs. Furthermore, untreated tumors may also give rise to secondary tumors, further complicating the situation and reducing treatment options.

Neurological Deficits

As mentioned earlier, the presence of a brain tumor can result in neurological deficits. These deficits can become more pronounced and severe over time if the tumor is not treated. The damage to brain tissue caused by the tumor can lead to permanent loss of function, partial or complete paralysis, and sensory disturbances such as vision or hearing loss. These neurological deficits can significantly impact an individual’s independence and quality of life.

Increased Risks of Complications During Treatment

Leaving a brain tumor untreated can also increase the risks and complications associated with treatment when intervention is eventually sought. Larger tumors may be more challenging to remove surgically, especially if they are located in critical areas of the brain. The size and location of the tumor can increase the risk of complications during surgery, such as bleeding or damage to healthy brain tissue.

Furthermore, as the tumor advances, treatment options may become limited. Tumors that have grown extensively or spread to other parts of the brain may be less responsive to therapies such as chemotherapy or radiation. This reduced effectiveness of treatment can further hinder the ability to manage the tumor effectively.


The consequences of leaving a brain tumor untreated can be severe and detrimental to an individual’s overall health and well-being. It is crucial to prioritize early detection and prompt treatment to minimize the potential complications and risks associated with brain tumors. Regular check-ups and timely intervention are key in managing brain tumors effectively and improving outcomes for individuals affected by this condition. If you suspect any symptoms or have concerns, consult a healthcare professional for proper evaluation and guidance.


  1. If your brain tumour can’t be cured
  2. If a Brain Tumor is Not Cancerous, Why Do Anything About …
  3. Complications of Brain Cancer Explained
  4. Glioblastoma Multiforme – Symptoms, Diagnosis and …
  5. Brain Tumors – Classifications, Symptoms, Diagnosis and …