Cancer is so hard to cure because cancer is your own cells growing wrong. This means the cells which make up the cancer are mostly just like all the other cells in your body. The problem with this is that it is very hard to target them for destruction. With microbes you can attack things which are only found in the virus or bacteria whereas cancers are just like all your other cells so if you attack them you normally kill other cells too. So what they do is target cells which grow fast, this does kill many cancer cells but it also kills other cells including hair cells as they grow a lot too this is why cancer patients hair falls out.
It’s hard to cure because the word we use for cancer is a huge catch-all for a multitude of disease and disease states. Since virtually all human tissue can generate cancer (usually through genetic mutation), the effect this has, or pathology, of the disease can be remarkably different. For this reason, there are ranges of treatments. On top of that, the treatments work in different ways – they kill cells, or kill ones which move in certain ways or grow too fast. The body is very complex, and drugs we make have to really be specific for the cancer, and not our good cells, and also have to pass through many layers of tissue (blood, muscle, bone, etc, etc), so its very complex indeed.. That is a very very short answer to your question 🙂
Great question! Like Pam says it’s so hard to cure cancers because really it’s caused when cells in our own body start going in to overdrive and making too many new cells. It’s really hard to just target the bad cells without damaging the good cells and like Pam says, that’s why some peoples hair falls out.
But we are getting a lot better at making specific treatments that will only target the bad cells. What we look for is certain compounds being made in the bad cells that are not present in good cells. If we know this, we can make drugs that will only act on the cells expressing that certain compound! In reality, the technology behind it is a lot more complex but I think that is about the jist of it.
Other things we’re starting to get really good at is preventing some sorts of cancers caused by viruses (like HPV) and also creating new technologies to detect sooner when people have cancer. Hopefully with these two new advancements and better treatments, we can make people who get sick with cancer feel a lot better, a lot sooner and with less side effects!!