What is a brain tumour?

Cancer starts in cells in our body. Cells are tiny building blocks that make up the organs and tissues of our bodies. They divide to make new cells in a controlled way. This is how our bodies grow, heal and repair. Cells receive signals from the body telling them when to divide and grow and when to stop growing. When a cell is no longer needed or can’t be repaired, it gets a signal to stop working and die.

What is a tumour?

Cancer develops when the normal workings of a cell go wrong and the cell becomes abnormal. The abnormal cell keeps dividing making more and more abnormal cells. These eventually form a lump (tumour). Not all tumours are cancerous. Doctors can tell if a tumour is cancerous by removing a small sample of tissue or cells from it. This is called a biopsy. The doctors examine the sample under a microscope to look for cancer cells.

A brain tumour that is not cancerous (benign) may grow but doesn’t usually spread to anywhere else in the brain. It may cause a problem by putting pressure on nearby tissue.

A brain tumour that is cancerous (malignant) can grow into nearby tissue. Cancer cells from the tumour may spread from where the cancer first started to other parts of the brain. Primary brain tumours do not usually spread to other parts of the body. Certain brain tumours may spread to the spinal cord.

Cells forming a tumour
Cells forming a tumour

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Back to Understanding brain tumours

Primary brain tumours

Primary brain tumours may be benign or malignant. There are several types of brain tumours.

How brain tumours are treated

Treatments for brain tumours include surgery, radiotherapy, chemotherapy and also drugs to treat symptoms. You may have a combination of treatments.

Secondary brain tumours

Secondary brain tumours happen when cancer cells spread to the brain from a cancer in another part of the body.