It's the news no one wants to hear, and following on from her father-in-law's own diagnosis, Kate's cancer would have been a hammer blow for the Princess of Wales and her family.

It came after her abdominal surgery in January. They would have carried out tests and that's when they would have discovered that cancer was present.

Today, she said she was undergoing preventative chemotherapy, that is in case there are any other cells that were left behind after the surgery, to make sure those are not the seeds of a cancer that grows back.

People who are in the early stages of cancer feel well, as Kate said she did. It is surreal to them that they're being told there are cancerous cells in their body that need dealing with. It takes a while for it to sink in.

In many ways the treatment can sometimes be harder to take, the side effects of chemotherapy can be tougher.

Chemo itself usually takes between three to six months and there will be rounds of treatments where she will be having drugs, normally through a pump straight into her veins. and that will go on round after round.

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There will be periods where she's not receiving any treatments and they are waiting to see the impact those drugs are having.

The effects can vary because these drugs target rapidly dividing cells, that's what cancer is, but they can also target things like rapidly growing hair follicles, the cells that produce blood platelets and white blood cells and so on. That is where the side effects come from.

So they can't go too hard and too fast just so that she can still function as a person.

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That is why we need to give huge understanding to Kate and what the family is going through. This is an awful lot to process. Cancer is still the diagnosis that no one wants to hear.

Even though the treatments have got much better and the outlook is much better than ever, it's still the dreaded diagnosis.