• Question: How does cancer start in a human body? And how long does it take for it to become serious?

    Asked by sarlotte to Gioia, Iain, Jo, Leo, Mariam on 23 Jun 2010 in Categories: .
    • Photo: Gioia Cherubini

      Gioia Cherubini answered on 21 Jun 2010:

      With one cell anywhere in the body going bonkers and starting dividing indefinitely. I don’t know how long it can take to become serious, I guess it depends on where the cancer starts and how big can it become before starting affecting the activity of the organs around

    • Photo: Mariam Orme

      Mariam Orme answered on 22 Jun 2010:

      Cells in your body are constantly growing and dividing. Since each cell needs a copy of your DNA, each time a cell divides it has to replicate its DNA. There are ‘proof-reading’ mechanisms to make this as accurate as possible, but sometimes mistakes slip through and the DNA ends up being changed slightly. This is what we call a mutation.

      Most mutations are harmless, and don’t actually make any difference. But some mutations cause cells to grow and divide more than they should; these cells grow out of control, and that’s cancer. So, cancer can start completely randomly as a result of this process. But there are factors that increase the likelihood of getting mutations. For example, chemicals in cigarette smoke or exposure to UV light can both cause DNA damage and mutations, meaning that they increase the risk of cancer developing. Also, some people inherit genes from their parents that make mutations more likely to occur, often by making the cell less able to correct mistakes in the DNA.

      How long it takes for a cancer to become very advanced varies a lot for each individual case, so I can’t really give you a good answer. But from the very first mutation, it usually takes a few years for advanced cancer to develop.

      That was quite a long answer, sorry – I hope it’s not confusing!

    • Photo: Iain Moal

      Iain Moal answered on 23 Jun 2010:

      Good question. Cancer starts when a cell it mutated in such a way that it starts dividing without control. The amount of time taken for it to become serious can vary a lot. Some cancers are very agressive and will become serious very quickly, others can take decades.

    • Photo: Joanna Watson

      Joanna Watson answered on 23 Jun 2010:

      Cancer starts in the human body from just one cell getting a mistake in it that makes it multiply out of control. Each of the new cells can also multiply out of control too until eventually there are loads of them and it is a cancer.

      It can take a REALLY long time for cancers to grow from a few broken cells, we don’t even know the longest time that it could take from the first broken cell to the cancer causing problems for the person it is in. We do know that some cancers grow really slowly probably take up to 20 years to get to the point where they cause symptoms. Some cancers grow much more quickly and can cause problems quite quickly too.