Cancer starts when cells change abnormally
WHAT IS CANCER
Cancer can start any place in the body. It starts when cells grow out of control and crowd out normal cells. This makes it hard for the body to work the way it should.
There are many types of cancer. It’s not just one disease. Cancer can start in the lungs, the breast, the colon, or even in the blood. Cancers are alike in some ways, but they are different in the ways they grow and spread.
The cells in our bodies all have certain jobs to do. Normal cells divide in an orderly way. They die when they are worn out or damaged, and new cells take their place. Cancer is when the cells start to grow out of control. The cancer cells keep on growing and making new cells. They crowd out normal cells. This causes problems in the part of the body where the cancer started.
Cancer cells can also spread to other parts of the body. For instance, cancer cells in the lung can travel to the bones and grow there. When cancer cells spread, it’s called metastasis (meh-TAS-tuh-sis). When lung cancer spreads to the bones, it’s still called lung cancer. To doctors, the cancer cells in the bones look just like the ones from the lung. It’s not called bone cancer unless it started in the bones.
The main categories of cancer
Our bodies are made up of billions of cells. The cells are so small that they can only be seen under a microscope. These cells are grouped together to make up the tissues and organs of our bodies. These cells are basically the same, but they vary in some ways. This is because the body organs do very different things. For example, nerves and muscles do very different things. So nerve and muscle cells have different structures.
Cancers can be grouped according to the type of cell they start in. There are 5 main categories
- Carcinoma – cancer that begins in the skin or in tissues that line or cover internal organs. There are a number of subtypes, including adenocarcinoma, basal cell carcinoma, squamous cell carcinoma, and transitional cell carcinoma
- Sarcoma – cancer that begins in the connective or supportive tissues such as bone, cartilage, fat, muscle, or blood vessels
- Leukaemia – cancer that starts in blood forming tissue such as the bone marrow and causes large numbers of abnormal blood cells to be produced and go into the blood
- Lymphoma and myeloma – cancers that begin in the cells of the immune system
- Brain and spinal cord cancers – these are known as central nervous system cancers
Cancers can also be classified according to where they start in the body, such as breast cancer or lung cancer.
EmoticonEmoticon