Why is cancer so hard to cure? Will we ever find an infallible cure?
In: 2088
Cancers are hard to cure because there are so many different ones. For example, the treatment/cure for lymphoma isn’t the same for glioblastoma.
There are many challenges to curing caner. Cancer is an entire subset of diseases, not just one. A lymphoma treatment may be entirely different than an adenocarcinoma in the bowel. Even then can vary from person to person with treatments differing due to random chance and genetics (this is relevant in a study that I’ll get to later).
Additionally, [the cure needs to also not kill the patient.](https://xkcd.com/1217/) Many cancers have a lot of overlap genetically, and physically with healthy cells. IIRC many of them can start off as normal cells, just losing the “stop growing signal” and then ending up in the wrong spots, like a mass from the arm sprouting inside lung tissue. So targeting them without also targeting healthy and vital structures is hard. It’s killing a small portion of something that is mostly human, inside of the human, without also killing the human.
Part of this is why you see sensational headlines like “new drug kills cancer!”
Okay it may kill cancer in a petri dish, but does it work in rats? Monkeys? Does it do this in rats or monkeys without also killing them or leaving them with debilitating and unethical diseases?
Or even if it does pass all of these, does the drug only actually work on a small subset of cancers?
[This trial made the rounds of reddit a few months ago.](https://www.nytimes.com/2022/06/05/health/rectal-cancer-checkpoint-inhibitor.html) Some cynics were saying “guess we’ll never hear of this drug again!!!”, even though it was 1, already a drug in common use for another cancer, and 2, how often are people keeping track of drugs that cure a subset of a subset of cancer. It worked on people with rectal cancer, who had a specific type that is only about 10% of rectal cancers, who also had a genetic abnormality. It may work for more, but that would require further study, but for the time, that still leaves 90% of the other colon cancers, which even then only make up a smaller percentage of all overall cancers. So even if one treatment comes out and has “solved” a specific type of cancer, in a specific area, in a specific type of person, that’s amazing but then it just becomes a treatment. It’s no longer news unless you’re in that field or have vested interest in it like a patient or family.
Usually, cells that cause disease are very different to your cells. Bacterial cells have very different characteristics to human cells and so we can use treatments that exploit those differences to only eradicate bacteria.
However, cancer results from mutated human cells, so cancer cells and human cells are overall very similar. Therefore, methods that eradicate cancer cells will often also eradicate human cells and we must rule them out. That makes it very hard to find a treatment.
Because cancer cells are very similar to human cells and trying to kill the cancer cells may also harm the patient. Also there are so many types of cancers that it is impossible to develop a single treatment / drug to cure all types of cancers.
To understand this there are a few things you need to know about cancer:
1. It’s not a virus or bacteria or parasite. It is a part of our own body that refuses to cooperate with the rest
2. Because of that it is hard to target directly. We can’t just use a drug that kill everything of a certain cell type because it would kill all the other cells making up our bodies.
3. There are good and bad tumors good ones just grow but leave us alone. Those are usually referred to as benign growth. They attack the body but can cause deformation.
4. Cancer is the bad type of tumor. It diverts blood to itself so it can grow on the expense of killing the oxygen and nutrient supplies of the other cells nearby causing them to die off while the cancer flourishes. (Which can finally result in death)
5. A cancer heavily compromises our immune system. The immune system is responsible for fighting of malicious bacteria, viruses and generally keeping our body’s in working order. So many time when people die of cancer it isn’t really the cancer that kills them but the fact that Thier bodies can’t fight of another disease because of the compromised immune system.
All of this results in the fact that no two cancers are the exactly the same which makes it really hard to develop a universal treatment. It’s not impossible but individual cancer treatments (created for one specific tumor) are way more promising but also extremely expensive since they can’t be mass produced.
Edit: To clarify individual treatments are more likely to result in a cure.
Cancer is not a single thing, it is a group of diseases where your own cell has abnormal and uncontrolled growth. There are differences depending on what cell types start as in your body.
It is hard to threat because it is your own cells that duplicate in an extreme rate. Your immune system will not in general attack it because it can see it is your own cells. If they would know the cells needed to be killed they could manage that, this is why cancer does not spread between people, your body identifies cells from another body as foreign and attack it regardless if they are cancerous or not.
This is why organ translation can be problematic too, there is immunosuppressant drugs to stop the immune system from attacking foreign cells. Cancer transmitted via transplants are possible but extremely rare.
Any medical intervention needs to kill the cancer cells but not kill normal cells or at least kill them at a lower rate. Because there is minimal difference between what you need to keep alive and what to kill it is very hard to do.
Killion cancer cells are not hard, the hard part is to do it in a host without killing the cells they need to survive.
If you compare to bacterial or viral infections they are in many ways different from our cells and medicine can target the difference.
Treatments like Chemotherapy exploit that they decided more often and cells target cells that divide. It results in less killing of cells you like to keep.
Radiation targets an area of the body and kills cells that are there. The problem cancer cell can spread out in the body and the radiation kills cells you what to keep alive. If the tumor is too close to something you need to stay alive just hitting the tumor can be impossible.
Surgery has the same problem as radiation, you can remove a large tumor but it can be impossible to remove enough around it to make sure all cancer cell is gone without killing the patient. Cancer cells can also migrate.
So cancer is a group of diseases where your own cells grow in an uncontrolled rate. It is because it is your cells threatening it is hard without killing the cells you need to survive.
So cancer is basically a cell that has mutated.
Let’s talk ninjas.
Cancer cells are ninjas. They’re made wrong. Usually when a cell is wrong it will kill itself, if not, the body guards (T cells) will kill it. But the cancer cell is a ninja, so the body guards can’t see or find it.
Because of this, the ninja goes on to replicate itself (mitosis), creating more ninja cells, until there’s so many that you have a lump of them (cancer tumour), which is still hidden from the body guards. Eventually some ninjas break away and start their own ninja school somewhere else in the body (secondary cancer).
As for treatment, let’s talk trees.
Our treatment is getting better and better, but for a long time it was like having one sick tree in the forest. We are not sure how to kill just one tree, so our only hope was to burn the whole forest and hope that the sick tree dies too.
As time goes on, we are getting better at using treatments that are more targeted to just the sick tree, but sometimes there are side effects to the forest still.
I hope this helps x
The biggest challenge is that cancer cells are human cells. They’re human cells that are malfunctioning.
If I have a bacterial infection, I need to find a way to kill bacteria without killing the human. This isn’t too tough.
If I have cancer, I need to find a way to kill human without killing human. This is very hard.
Moreso, I need to find a way to *reliably* kill human without killing human. This is ‘multi-billion dollars of research’ hard.
[Relevant XKCD ](https://xkcd.com/1217/)
Side note: this is why chemotherapy can have such severe side effects: it’s killing human, and not killing human (but making human very unwell because it still has to kill human)
The treatment has to be tailored to the patient to have any chance of success. This makes it difficult to research and expensive to produce. If the cancer is not detected early, and spreads to other organs, the chance of a successful treatment is very much less.
“Cancers” are a thing like “Colds” are a thing.
There’s 1000000’s of them.
We can cure many of the types of cancers, but not all of them, yet.
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