• Question: How does cancer form in your body?

    Asked by Michelle Mc Kiernan to Colin, John, Kevin, Shikha, Triona on 18 Nov 2014. This question was also asked by josh, Leahgrealish.
    • Photo: Shikha Sharma

      Shikha Sharma answered on 18 Nov 2014:

      Hi Michelle Mc Kiernan,

      The human body is made up of billions of cells. All cells have a lifecycle where they are born, gets old and die after a certain amount of time. Replication ensures that new cells are made to take their place. Now if these cells forget to die then there will be a space problem in our body because old cells are still there and new cells are also generating. When the cells start to divide uncontrollably, forming lumps or growths, then we call it as cancer. Growths like this are called tumours. Benign tumors aren’t cancerous. Cells in benign tumors do not spread to other parts of the body. Malignant tumors are cancerous. Cells in these tumors can invade nearby tissues and spread to other parts of the body.

    • Photo: Kevin Motherway

      Kevin Motherway answered on 18 Nov 2014:

      The really amazing part about life is that it is a self replicating molecule. All cells in your body contain the entire blueprint to make another you: We call it DNA! So when you cut yourself you’ve got platelet cells that help clot the blood and seal the wound in a scab. White blood cells arrive to kill off any infections that might have got in and to clean away any debris and reabsorb the nutrients that are lying around at the scene of the accident. The the skin cells and and muscle cells damaged start to replicate according to the DNA recipe and you generate more tissue to repair the damage, all under the seal of the scab. While this self replicating is going on mistakes can happen in transcribing the DNA and this is how cancers can happen, white blood cells will often spot the defective cells and wipe the out but if they become established a tumour can form: and this is now UV light burns on your skin from the sun can result in skin cancers. So basically when the rewriting of DNA does wrong it can form cancers. Things that make the rewriting process generate errors are known as mutagens (or specifically for cancer mutations: carcinogens) and can be either things like radiation (like UV light) or even chemicals like Benzenes inhaled in cigarette smoke. Cigarettes are just chock full of carcinogens and risk of all types of cancers go way up for smokers. If you’ve started smoking stop as soon as possible!