Question: why won't there be one cure for all cancers?

Kiran Meekings answered on 17 Mar 2010:

Not very many people actually know what cancer is so I’ll explain (you’re going to look well clever around the dinner table tonight!). Your body is made of billions of cells that all know exactly where they’re supposed to be, how they’re supposed to act and when they’re supposed to die. Sometimes they go wrong though: If they forget when to die or go to the wrong place or do the wrong thing, you end up with a big clump of cells somewhere it’s not supposed to be. That’s called a tumour. Sometimes tumours are benign which means you can cut them out and you’ll be fine. Sometimes though they have the potential to kill you and we call those malignant tumours, or cancer.

So that’s cancer, but why can’t we cure it with one drug? The problem is that each of us has about 25,000 genes. People think you need about 7 of those genes to go wrong to turn a cell into a cancerous cell (which might then make a tumour). So how many different types of cancer can you have then? Approximately 1.5 x 10^30 using those numbers…. So instead we try and get one drug that treats all types but of course, that’s not going to work. It’s a bit like buying one pair of shoes of size 5 and making the whole world wear them. They’ll fit some people but not everyone. So, what we’re trying to do as scientists is to find as many different drugs to treat as many different types of cancer as possible. We call that tailoring therapy or personalising care – you’ll hear a lot more about that in the next few years in drug development!