One in three of us are estimated to get some form of cancer at some point in our lives. In fact, various experts think that this ratio may increase to one in two in the coming decades.

At any rate, it is likely that every family will come into contact with this disease directly or indirectly. 

5,000 people are diagnosed with cancer every week in the UK, and whilst different cancers are more prevalent at different ages, the overall risk of getting cancer rapidly increases as we get older.

Cancer explained

The word 'cancer' does not refer to one single disease but a group of related diseases that share a common factor.  That factor is our cells, the tiny building blocks which group together to form the various tissues and organs that make up our bodies. 

Normally, cells grow and divide in an orderly, regulated way  they may perform specific functions for a while, depending on their location in the body - and often they have a limited life span. 

Generally, this carries on in a systematic process.  However, cancer cells are different.  Somehow they become released from this usual control and keep on dividing and multiplying, unregulated by their environment. Instead of dying, they keep growing, eventually forming a mass of unwanted tissue called a tumour. 

By the time it is big enough to be seen on a scan or felt as a lump, there are already millions of cells present in the tumour.  As well as growing in the tumour, some of the cancer cells may break away and spread further afield. 

There are as many types of cancer as there are types of cell  about 200.  Each gives different symptoms, has different causes and responds differently to treatment.

Written by Dr. Anna Tilley 

03/06/2009