Examine Yourself: What is cancer? An explanation for children and teens

CANCER can refer to many different diseases and the terminology can be quite confusing. In this week’s column, I hope to simplify and explain what cancer is, how it may be treated, and even how long it has been around.

How many types of cancer are there?

We have about 100 trillion cells in our bodies and they all have a specific job. From skin cells, to brain cells, to lung cells, we have more than 200 different types.

Cancer is a disease of the cells and because we have 200 different types of cells we have 200 different types of cancer.

We usually name cancer based on the type of cell or tissue in which the cancer has developed; so if lung cells start to grow out of control, it is called lung cancer; and if skin cells become cancerous, then we refer to it as skin cancer.

Healthy cells and not so healthy cells

The cells in our bodies are very well-controlled and are very good at what they do. They adapt to their specific role in the body, they work really hard, and, eventually, they die off and get replaced by new cells. Cells are constantly dying in our bodies and being replaced by new cells and that is normal and healthy.

Each cell has something called a nucleus, which is like the control centre for the cell. Inside the nucleus is the DNA. This is the code that tells the cell what to do, and eventually it controls the death of the cell. This normal and controlled cell death is called apoptosis. Cancer is what happens when this system goes wrong and when a cell doesn’t die off when it should. It is the uncontrolled, abnormal growth of cells and is usually due to damaged or faulty DNA. These cells grow into large clumps, called tumours.

Tumours

Tumours usually cause problems in the body in one of two ways: either directly, by putting pressure on nearby organs or tissue, or indirectly, when some tumour cells break off and invade other areas of the body, spreading the cancer.

Tumours can be benign or malignant; benign tumours do not invade surrounding tissue or spread around the body. Malignant tumours may invade or spread.

If cancer is a disease, then is it contagious?

Lots of human diseases are caused by something from outside our bodies, like a bacteria or virus, coming into our bodies and making us ill.

But cancer is not like that. Cancer starts inside our own bodies, when our cells stop behaving like they should and this is what causes the symptoms of the disease.

This means that cancer is not contagious: we can’t catch it from another person.

Treating cancer

Some cancers are more easy to treat than others. There are three main types of treatment and the medical team will decide which one, or which combination of treatments, will work best for each cancer patient.

The tumour may be removed by surgery or the cancer may be treated with special chemicals, a treatment called chemotherapy. Another type of treatment is called radiotherapy and this is when the cancerous cells are bombarded with high-energy rays.

Cancer is not a new thing

Cancer has been around for a long time; it has been found in 3000-year-old human remains; even dinosaurs had tumours.