Cancer Informative Speech

When people hear the word cancer, they think of a terrifying, life threatening disease. Have they ever thought of how it even started? Cancer cells grow and spread throughout the body in many ways, and sure you can catch it early but not usually. Cancer spreads to many things in and on the body, not just where the cancer is, but especially all of the bloodstreams in your body.

How Cancer Cells Grow and Spread The place where cancer starts to grow is called the primary site. Although some cancers may spread to more than one area of the body to form multiple secondaries or metastases. In order to spread, some cells from the primary cancer must break away, travel to another part of the body and start growing there. Cancer cells don't stick together
as well as normal cells do. They may also produce substances that stimulate them to move. Cells become abnormal if their DNA – and therefore their "knowledge" – becomes damaged. As long as there are very few abnormal cells and they are kept under control by our immune system, they will not harm us. It is only when these cells start to divide uncontrollably, forming lumps or growths, that we have one of the more than 200 diseases called cancer. Growths like this are called tumors (“How Cancer Can Spread”, cancerresearchuk.org).

Bloodstream and Cancer One of the major places in the body that gets affected by cancer cells is the blood stream.
If the cancer cells go into small blood vessels they can then get into the bloodstream. They are called circulating tumour cells. Researchers are currently looking at using blood tests to find circulating tumour cells to diagnose cancer and avoid the need for tests such as biopsies. They are also looking at whether they can test circulating cancer cells to predict which treatments will work best for each patient. The circulating blood sweeps the cancer cells along until they get stuck somewhere. Usually they get stuck in a very small blood vessel called a capillary. Out of many thousands of cancer cells that reach the blood circulation only a few will survive to form a secondary cancer or metastasis. Some cancer cells are probably killed off by the white blood cells in our immune system. Others cancer cells may die because they are battered around by the fast flowing blood. Cancer cells in the circulation may try to stick to platelets to form clumps to give themselves some protection. Platelets are blood cells that help the blood to clot. This may also help the cancer cells to be filtered out in the next capillary network they come across so they can then move into the surrounding tissues (“How do Cancer Cells Grow and Spread?”,
ncbi.nlm.nih.gov).