What Is Metastasis And Can it Affect Brain Tumour Treatment?

Treatments for cancer need to be personalised for every person, because there are countless factors which can affect how cancer can be treated.

Everything from the location and size of a tumour to its rate of expansion or effects on a person can all alter the course of treatment and shape the approach your cancer team will take to take care of you.

One aspect of this, which is particularly important to note, is a metastatic tumour, which can fundamentally change how a cancer is treated and often requires coordination with oncologists who specialise in treating cancers in different parts of the body.

What is a metastasis? How does it differ from other brain tumours? And how can it affect your treatment?

What Is A Metastasis?

A metastasis or secondary tumour is a tumour that starts somewhere else in the body before spreading somewhere else. Many, if not most, cancers can metastasise and spread to another part of the body, although the likelihood of this depends on the type of cancer.

There are typically three ways in which a tumour can metastasise and spread to another area of the body:

• It can grow into the tissues and organs around the tumour and grow into another area.
• Cancer cells can break off and travel through the bloodstream to spread to other areas.
• It can spread from one lymph node to another through the lymphatic system.

Whilst a metastatic tumour can spread throughout the body, as specialists in neuroscience and neurosurgery, we provide diagnostics and treatments designed to help treat metastatic brain tumours and the complexities that can come from them.

What Are The Most Common Types Of Metastatic Tumours?

Outside of cancers which do not spread, such as basal cell carcinoma, most malignant cancers have the potential to metastasise. However, the most common tumours to metastasise include:

• Breast cancer
• Lung cancer
• Ovarian cancer
• Prostate cancer
• Oesophageal cancer
• Stomach cancer
• Skin cancer
• Pancreatic cancer

Where Does Cancer Metastasise?

Exactly where a cancer metastasises can vary depending on the original tumour’s location, and whether it is easier for it to grow into other tissue or spread via the lymphatic system. However, some common metastatic sites other than the brain include:

• Bones
• Liver
• Lungs
• Lymph nodes
• Adrenal glands

How Does A Metastatic Brain Tumour Differ From A Primary Tumour?

The main difference between a primary and metastatic tumour is where it originates, but this simple distinction can fundamentally change how your cancer team will manage your treatment.

A primary brain tumour starts in the brain, most commonly the cerebrum, although there are cancers that begin in the spinal cord, pituitary gland or the meninges, which are layers of tissue which protect your central nervous system.

By contrast, secondary brain tumours form elsewhere in the body and spread to the brain, typically as cancer cells break away from the primary tumour and flow through the bloodstream to the brain, where they are deposited and form new tumours.

Metastatic brain tumours are generally more common than primary brain cancer, and cancer teams will typically check for metastases if you have been diagnosed with a type of cancer that has a chance of spreading to the brain.

How Does A Metastatic Tumour Affect Brain Cancer Treatment?

Despite being located in the brain, a metastatic tumour has the properties and the required treatments of the original primary tumour. A lung cancer tumour that spreads to the brain needs to be treated in the same way as lung cancer and not a brain tumour, which originates in the brain.

Exactly how it is treated depends on where it originated, where the tumour(s) are located, how large they are, how aggressively they are growing, and the overall health of the person being treated.

There are various treatment options available, but the primary treatment we will often use is stereotactic radiosurgery.

Stereotactic Radiosurgery

Stereotactic radiosurgery, sometimes known as Gamma Knife radiosurgery, is a precise form of radiotherapy where beams of radiation are coordinated to focus on a specific part of the body, ensuring the maximum amount of radiation hits the tumour with much lower doses affecting surrounding tissue.

It is primarily used for brain tumours because there is less of a chance of the brain or the tumour moving, allowing for much more precise and aggressive treatment planning than other forms of radiotherapy.

It is typically undertaken in a single one-day session, taking between one and four hours depending on the complexity of treatment.

Alternative Treatments

• Chemotherapy
• Targeted medicines
• Immunotherapy
• Conventional surgery
• Whole-brain radiotherapy

Explore the Queen Square website to learn more about our advanced radiotherapy and neurosurgical treatments for metastatic brain tumours, as well as advanced diagnostics and second opinions.