What cancer is
Cancer is a disease caused by normal cells changing so that they grow in an uncontrolled way.
The uncontrolled growth causes a lump called a tumour to form. If not treated, the tumour can
cause problems in one or more of the following ways
Spreading into normal tissues nearby
Causing pressure on other body structures
Spreading to other parts of the body through the lymphatic system or bloodstream
There are over 200 different types of cancer because there are over 200 different types of body
cells. For example, cells that make up the lungs can cause a lung cancer. There are different
cells in the lungs, so these may cause different types of lung cancer.
Normal cells
Your body is made up of billions of cells that can only be seen under a microscope. These
cells are grouped together to make up the tissues and organs of our bodies. They are a bit like
building blocks.
Different types of body tissues are made up of different types of body cells. For example, there
are bone cells in bone and breast cells in the breast.
Genes and cancer
Different types of cells in the body do different jobs, but they are basically similar. They all
have a centre called a nucleus. Inside the nucleus are the genes. Genes are really bits of code.
The information they carry can be switched on or off. The genes control the cell. They decide
when it will reproduce, what it does and even when it will die.
Normally the genes make sure that cells grow and reproduce in an orderly and controlled way.
If the system goes wrong for any reason, the usual result is that the cell dies. Rarely, the system
goes wrong in a way that allows a cell to keep on dividing until a lump called a 'tumour' is
formed.
Benign and malignant tumours
Tumours (lumps) can be benign or malignant. Benign means not cancer. Benign tumours
Usually grow quite slowly
Do not spread to other parts of the body
Usually have a covering made up of normal cells
Benign tumours are made up of cells that are quite similar to normal cells. They will only cause
a problem if they
Grow very large
Become uncomfortable or unsightly
Press on other body organs
Take up space inside the skull (for example, like a brain tumour)
Release hormones that affect how the body works
Malignant tumours are made up of cancer cells. They
Usually grow faster than benign tumours
Spread into and destroy surrounding tissues
Spread to other parts of the body
The diagram below shows a tumour appearing in cells lining a body structure such as the
bowel wall. The tumour grows through the layer holding the cells in place (the basement
membrane) and spreads into the bloodstream.
It is the ability to spread that makes a cancer harmful. If a cancer is not treated, it can spread
into the organs near to where it started growing. It can also damage other parts of the body that
it spreads to.
Primary and secondary cancer
The place where a cancer begins is called the 'primary cancer'. Cancers may also spread into
nearby body tissues. For example, lung cancer can spread to the lining of the chest, the pleura.
Ovarian cancer can spread to the lining of the abdomen (the peritoneum). This is called
locally advanced cancer.
Cancer cells can break away from the primary tumour and be carried in the blood or lymphatic
system to other parts of the body. There they can start to grow into new tumours. Tumours from
cancers that have spread are called 'secondary cancers' or 'metastases' (pronounced
met-as-tah-seez). A cancer that has spread has 'metastasised'.
The various organs of the body are made up of different types of cells. Any of these cell types
can grow into a primary cancer. Different types of cancer behave very differently. The type of
cancer affects whether it is
Likely to grow quickly or slowly
Likely to produce chemicals that change the way the body works
Likely to spread in the blood or lymph system
Likely to respond well to particular treatments
Cancer symptoms
Cancers can cause different symptoms according to where they are in the body. A cancer may
press on a nerve, or another nearby body organ. It may also cause symptoms by releasing
chemicals or hormones into the bloodstream. You can find out about the symptoms for each
type of cancer in our section about specific cancers.
Information courtesy of Cancer Research. For more information please consult their website.
Cancer is a disease caused by normal cells changing so that they grow in an uncontrolled way.
The uncontrolled growth causes a lump called a tumour to form. If not treated, the tumour can
cause problems in one or more of the following ways
Spreading into normal tissues nearby
Causing pressure on other body structures
Spreading to other parts of the body through the lymphatic system or bloodstream
There are over 200 different types of cancer because there are over 200 different types of body
cells. For example, cells that make up the lungs can cause a lung cancer. There are different
cells in the lungs, so these may cause different types of lung cancer.
Normal cells
Your body is made up of billions of cells that can only be seen under a microscope. These
cells are grouped together to make up the tissues and organs of our bodies. They are a bit like
building blocks.
Different types of body tissues are made up of different types of body cells. For example, there
are bone cells in bone and breast cells in the breast.
Genes and cancer
Different types of cells in the body do different jobs, but they are basically similar. They all
have a centre called a nucleus. Inside the nucleus are the genes. Genes are really bits of code.
The information they carry can be switched on or off. The genes control the cell. They decide
when it will reproduce, what it does and even when it will die.
Normally the genes make sure that cells grow and reproduce in an orderly and controlled way.
If the system goes wrong for any reason, the usual result is that the cell dies. Rarely, the system
goes wrong in a way that allows a cell to keep on dividing until a lump called a 'tumour' is
formed.
Benign and malignant tumours
Tumours (lumps) can be benign or malignant. Benign means not cancer. Benign tumours
Usually grow quite slowly
Do not spread to other parts of the body
Usually have a covering made up of normal cells
Benign tumours are made up of cells that are quite similar to normal cells. They will only cause
a problem if they
Grow very large
Become uncomfortable or unsightly
Press on other body organs
Take up space inside the skull (for example, like a brain tumour)
Release hormones that affect how the body works
Malignant tumours are made up of cancer cells. They
Usually grow faster than benign tumours
Spread into and destroy surrounding tissues
Spread to other parts of the body
The diagram below shows a tumour appearing in cells lining a body structure such as the
bowel wall. The tumour grows through the layer holding the cells in place (the basement
membrane) and spreads into the bloodstream.
It is the ability to spread that makes a cancer harmful. If a cancer is not treated, it can spread
into the organs near to where it started growing. It can also damage other parts of the body that
it spreads to.
Primary and secondary cancer
The place where a cancer begins is called the 'primary cancer'. Cancers may also spread into
nearby body tissues. For example, lung cancer can spread to the lining of the chest, the pleura.
Ovarian cancer can spread to the lining of the abdomen (the peritoneum). This is called
locally advanced cancer.
Cancer cells can break away from the primary tumour and be carried in the blood or lymphatic
system to other parts of the body. There they can start to grow into new tumours. Tumours from
cancers that have spread are called 'secondary cancers' or 'metastases' (pronounced
met-as-tah-seez). A cancer that has spread has 'metastasised'.
The various organs of the body are made up of different types of cells. Any of these cell types
can grow into a primary cancer. Different types of cancer behave very differently. The type of
cancer affects whether it is
Likely to grow quickly or slowly
Likely to produce chemicals that change the way the body works
Likely to spread in the blood or lymph system
Likely to respond well to particular treatments
Cancer symptoms
Cancers can cause different symptoms according to where they are in the body. A cancer may
press on a nerve, or another nearby body organ. It may also cause symptoms by releasing
chemicals or hormones into the bloodstream. You can find out about the symptoms for each
type of cancer in our section about specific cancers.
Information courtesy of Cancer Research. For more information please consult their website.
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
and Help.
