What is cancer?

Cancer forms when cells in the body start to multiply in an uncontrolled way.

This can form a lump or swelling (a tumour) or affect the way cells work, for example, blood cancers.

Cancer is not just one disease. There are over 200 different types, all with different signs and symptoms.

Treatments for cancer will be specific to the type of cancer.

Benign or malignant tumours

Tumours can be benign or malignant:

  • Benign tumours – are usually harmless and don't always need treatment
  • Malignant tumours – are cancer and will usually need some form of treatment.

Primary and secondary cancer

Cancer may be described as primary or secondary:

  • Primary cancer – where the cancer starts
  • Secondary cancer – when a primary cancer has spread to other parts of the body. It is also called metastatic cancer.

Living with cancer

Getting better from cancer depends on what type of cancer it is, how early it is diagnosed and if it has spread.

Many people have treatment for cancer and it doesn’t come back. For others, cancer can be kept under control for many years.

Research into cancer is evolving with new ways of treating and preventing cancer being discovered all the time. 

Maggie's is here with you

Our Cancer Support Specialists are here to listen to your concerns and help you find the information and help that's right for you:

Last review: Oct 2021 | Next review: Oct 2022

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