The word tumour means lump and may be used to describe any swelling, and although there are different
types of cancer it does not mean that the growth is a cancer (a malignant tumour), most lumps or tumours
are not cancers (benign tumours).
So what is it that decides whether a lump is a benign tumour or is a cancer? This is not always an easy
question to answer; malignant tumours have certain feature which makes them easier to recognise:
1. Cells grow in a disordered fashion- more than are needed to replace dead cells
2. The clumps of cells grow into nearby structures; they invade these structures and grow out of the organ
they have arisen from.
3. The cells can grow along nerves, and grow into blood vessels and lymphatic vessels
4. Cells can break off the parent tumour and travel across the cavities in the body (for example, the
cavity in the tummy where all abdominal organs lie)
5. Cells invade blood and lymphatic vessels so little collections of abnormal cells can travel to different
parts of the body
Benign tumours share none of these characteristics. Although benign tumours can grow very large, they
remain in the original organ even though the lump might get quite squashed. Benign tumours do not invade
other structures and do not travel to different parts of the body.
In practice, the difference between benign and malignant cells can be very slight, which is why doctors
need to do a range of tests to reach a decision. The only way that a doctor can be sure of the difference
between a malignant and a non- malignant tumour is by examining a part of the lump under a microscope, to
see the pattern of growth and to look at the cells in fine detail. With the different types of cancer this
is especially important to do.
As part of your curiosity about the disease you may wonder how it came to be named, the word originates
from Roman times when ancient writers described an incurable ulcer-like disease that spread into a shape
resembling a crab, 'cancer' is the Latin word for crab, other words you will frequently hear and read are
'tumour' meaning lump, 'neoplasm' meaning new tissue and 'oncology' which means the study of swellings, an
'oncologist' is a doctor specialising in cancer treatment, another word 'carcinoma' has entered our
language, taken from the writings of Hippocrates and meaning a malignant growth.
So as you can tell there are many different types of cancer in the world today but not all of them are
fatal.