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They key points covered in this video include:
1. What is cancer?
2. The different types of tumours
3. Risk factors for cancer?

What is Cancer?

Cancer is the result of changes in cells that lead to uncontrolled cell division. Cells divide through mitosis. This is normally very carefully controlled. The body normally only produces the amount of cells it needs. This is controlled by genes in the DNA. Cancer occurs when cells divide uncontrollably. The cell continues to grow and forms a group of cells of tumour. The tumour can damage the area surrounding it.

The Different Types of Tumours

Not all tumours are cancerous. There are two different types: malignant tumours and benign tumours. Malignant tumours can cause cancer. This is when cells break off from the tumour and go into, or invade, the surrounding tissue. These cells form another, secondary, tumour. These can be fatal as they destroy healthy tissue. Benign tumours stay in one place. They are not cancerous or fatal as they do not destroy healthy tissue.

Risk Factors for Cancer
The way you live can increase the risk of getting cancer. Having certain risk factors increases the risk of getting cancer - these include smoking, obesity and UV exposure. Smoking increases the risk of cancer in your lungs as well as elsewhere. Obesity is when your body mass is much higher than it should be. It is linked to bowel, liver and kidney cancer. The sun emits UV radiation. Being exposed to this can increase your risk of skin cancer. This means sun beds and not using sunscreen can increase your risk of getting cancer. You can be more likely to get cancer because of your genes. However, having risk factors doesn't mean you'll definitely get cancer - you are just more likely to.

Summary

1. Cancer is when there are changes in cells that result in uncontrolled cell division
2. The cells that divide uncontrollably form tumours
3. Tumours can either be benign or malignant
4. Benign tumours are not harmful, malignant tumours are
5. Certain risk factors, such as smoking, obesity and exposure to UV radiation, can increase the chance of getting cancer

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