Cancer is a disease where the normal regulation of cells in the body is broken and they grow abnormally. A healthy cell will replicate itself to replace old cells that die. But if a cell’s DNA is damaged, the cell won’t work properly.
The cell may replicate uncontrollably or not die when it should and become a tumour. These tumours can form in many different parts of the body, which is why there are so many different types of cancer.
The most common cancers in the UK are breast and prostate.
But many ould be prevented if everyone was healthier by not smoking and by maintaining a healthy weight, being active and eating a healthy diet.
Globally, lung cancer is the most common, closely followed by breast cancer.
Cancers are usually named after the organ in which they start, for example bowel cancer. However, some cancers spread, either locally (into the tissues surrounding the cancer) or into other parts of the body – a process called metastasis.
This happens when cancer cells break away from the tumour and move through the bloodstream or lymphatic system.
They can end up in another organ such as the liver or lungs, and begin replicating to form another tumour.
The main reason that cancer rates are increasing is because people are living longer; the older you are, the more likely you are to develop cancer.
However, increasing rates of obesity and physical inactivity, the rise of smoking in low- and middle-income countries, and people eating unhealthy diets are also contributing to a rise in preventable cancers.
There is no single food or ingredient that will have a large impact on whether you do or don’t get cancer. Rather, the regular patterns of what we eat combine to make us more or less susceptible to cancer.
For example, eating lots of fruit, vegetables, beans, pulses and wholegrains lowers your risk of cancer, but eating too much red or processed meat increases your risk of bowel cancer.
Eating too much food that’s high in fat or sugar tends to lead to excessive calorie intake and weight gain, which itself is a cause of several types of cancer.
In addition, alcohol (from any type of alcoholic drink) increases the risk of several cancers.
Anyone can get cancer, but a small number – about 5-10% – are strongly inherited, meaning they are passed from parents to child.
One example is a certain type of breast cancer that occurs due to mutations, or errors, in two genes: BRCA1 (BReast CAncer gene one) and BRCA2 (BReast CAncer gene two).
However, inheriting a mutated gene does not mean you will definitely get that cancer; rather that you have a higher risk.
Cancer can be treated in different ways including surgery, radiotherapy, chemotherapy, immunotherapy, targeted therapy and hormone therapy.
Most people will have a combination of these, and people with the same cancer may receive different treatment based on:
Cancer drugs, such as chemotherapy, kill cancer cells in different ways, such as by attacking the DNA, which stops the cell replicating and so it eventually dies.
But chemotherapy can make people feel very poorly because the drug cannot tell the difference between cancer cells and healthy cells.
This can lead to side-effects such as nausea and hair loss.
Survival rates and prognosis depend on the cancer, the stage and the health of the person. However, pancreatic cancer has the lowest survival rate in the UK, mainly because it’s usually not discovered until it’s quite advanced.
Cancer is categorised into different stages depending on how large the tumour is and how far it has spread:
Usually, the earlier cancer is diagnosed, the better the chance of treatment being effective. However, stage IV cancer can still be treated to prolong survival and improve quality of life.
Each cancer is different, which is why we generally don’t talk about ‘curing cancer’. However, advances in treatment and technology mean we are closer than ever to being able to remove all traces of certain cancers from someone’s body.
Known as complete remission, this could be considered a cure.