Understanding Key Terms You Might Hear During A Diagnosis

Understanding Key Terms You Might Hear During A Diagnosis

Being diagnosed with a neurological condition is a position that no one wants to be in. The shock and disruption to your daily life can be tough to deal with, and at the same time you will be faced with a lot of medical terminology that might be unfamiliar and intimidating.

Our specialist teams at our Gamma Knife centres in London and Sheffield understand the importance of helping patients feel well-informed and reassured at this difficult time. We have highly trained clinical nurse specialists (CNSs) who will be your first point of contact, and are able to explain your diagnosis in clear language.

However, words such as “lesion”, “tumour” and “mass” that you might hear or read about during your diagnosis can be alarming. Here’s a closer look at what they mean, and some other terms you might hear.

What is a “lesion”?

In medical language, a lesion simply means an area of abnormal tissue. It doesn’t automatically mean “cancer” or even “tumour.” Lesions can be caused by many different things, such as infection, inflammation, injury, or abnormal growth of blood vessels.

Think of the word “lesion” as a broad umbrella term: it describes that something looks different from normal on a scan, but is not a specific diagnosis. Further tests, such as MRI or CT scans, may be required to help doctors understand the cause and whether treatment is needed.

Examples of brain lesions that are not tumours:

• Arteriovenous malformations (AVMs):tangles of abnormal blood vessels in the brain that can increase the risk of bleeding.
• Cavernomas:clusters of small, abnormal blood vessels that may cause seizures or headaches. They’re sometimes known as cavernous angiomas, cavernous hemangiomas, or cerebral cavernous malformation.
• Areas of scarring (gliosis):often left after injury, stroke, or multiple sclerosis.
• Inflammatory lesions:for example, patches of inflammation in conditions like multiple sclerosis.
• Cysts: fluid-filled sacs that can show up on scans but are not cancerous.

All of these are considered “lesions,” but they are not tumours, and may or may not require treatment.

What is a “mass”?

The term “mass” is another word that can sound frightening, but again, it doesn’t automatically mean something dangerous. A mass simply means a lump or collection of tissue that looks different from surrounding tissue.

A mass may be benign (not cancerous), such as a meningioma (a common type of non-cancerous brain tumour). A mass may also be malignant (cancerous), meaning the cells can grow and spread more aggressively. Sometimes, what appears as a “mass” on a scan may turn out to be a cyst filled with fluid.

The word “mass” is descriptive rather than diagnostic — it tells doctors something is there, but not yet what it is.

Benign vs. malignant: the key difference

These two terms are often used to describe brain tumours or growths:

• Benign tumours grow slowly, usually stay in one place, and do not spread to other parts of the body. While they can still cause symptoms (because the skull is a tight space and any growth can put pressure on the brain), they are not cancerous.
• Malignant tumours are cancerous. They tend to grow faster, may spread, and usually require more urgent or intensive treatment.

Understanding this difference helps patients see why a diagnosis of a benign tumour may still require direct treatment, or it may be managed with a “watch and wait” approach of careful monitoring. The patient will usually have regular MRI scans, and the results will be carefully analysed for any sign that the tumour or lesion is growing or causing issues.

Other terms you might hear

When discussing diagnosis and treatment, doctors often use terms that are second nature to them but unfamiliar to patients. Here are a few you might come across:

• Primary tumour:A tumour that starts in the brain rather than spreading from elsewhere in the body.
• Metastasis (or secondary tumour):A cancer that has spread to the brain from another part of the body, such as the lung or breast.
• Invasive vs. non-invasive:Invasive procedures involve surgery and entry into the body. Non-invasive, such as Gamma Knife treatment, does not involve cutting, stitches, or a hospital stay.
• Radiosurgery:Despite the name, no scalpel is used. It refers to highly precise radiation beams used to treat abnormal tissue. This is a type of radiotherapy, delivered very precisely in one session in most cases.

Hearing these terms without explanation can leave patients feeling anxious or confused. That’s why we believe clear communication is essential in healthcare, to help patients and families focus on understanding their condition and make informed decisions about treatment.

Centres of Excellence for Stereotactic Radiosurgery treatment of complex Brain Tumours