To be clear, I’m completely unburdened by any oncological knowledge to the point where I’m not even sure if I’m asking the right question. I’m just curious why it is so difficult to cure cancer once it has metastasised. What kinds of hurdles are standing between us and a cure?
Thanks in advance.
In general, it’s very,very difficult to target a particular type of cell. When cancer has spread throughout the body, it’s almost impossible to kill those cells without killing the patient.
Right, even though chemotherapy and the like is tailored as much as possible to target only the cancer cells, one of the methods used for targeting is just location. If the cancer’s all in one compact lump, then the most straightforward treatment is to just cut out that lump (or maybe the body part containing the lump, if it’s something you can live without). With radiation, you aim it so that the radiation is most intense at the location of the cancer. Even drugs are often activated in some way only at particular locations. Once it spreads, that tool is no longer available, so the treatments become less specific, and you end up either killing less cancer, or more of the patient.
Also, cancer cells mutate since they divide so rapidly and since the normal quality controls on the duplicated DNA are often missing or impaired. Mutations that allow them to pump out chemo drugs, stimulate growth of new blood vessels and a million other beneficial (for the cancer cell) traits means that even if you have a drug that works on most of the cancerous cells, it probably won’t work on all of them. So initially you get some degree of remission, but then the cancer bounces back - often with a vengeance.
Not to mention that once the cancer spreads the time left to live, and therefore the time available to successfully kill the cancer, becomes much shorter.
New methods for targeting cells are developing all the time. I’ve had cancer twice (just got the “all clear” on the second round this week, in fact). The first time was lymphoma, which had gone systemic. That meant that it couldn’t be treated by simply cutting it out. I underwent chemotherapy, but also had monoclonal antibody treatment. Essentially, they had cloned antibodies from the blood of a rodent that was naturally immune to non-Hodgkins large b-cell lymphoma. They injected me with those antibodies, which targeted and destroyed my infected b-cells. It worked 
One of the core areas of cancer research is just figuring out how to target individual cancer cells within the body. It’s quite complicated.
Hence the ‘early detection’ push and how this correlates to success.
Breast cancer is a great example, because if there is a defined spot or two in the breast(s), and you are essentially at Stage 1 or 2 of the four stages, you can target the treatment and follow up with a broad treatment of chemo and radiation that further attacks the site and more of the body in general.
Because the cancer was not advanced, metastisized or spread, the patient is in better health and better able to withstand everything that comes with fighting cancer.
Gary: WOW, good for you. Simply awesome.
I have the misfortune of growing up in a cancer cluster ( I am 43 now), and I’ve about had it with friends/family from my old neighborhood in Philadelphia dying of non-hodgkin’s lymphoma and leukemia in their 30’s and 40’s. These cancers are incredibly hard to target, because they pretty much spread all over. The patient is gravely ill from having cancer all over and the treatment needs to be overwhelming and very broad, compounding the problem.
Sounds like Gary’s particular cells could be targeted, which is a huge break.
Some doctor, whose name I don’t recall, in an article several years ago said that in his opinion, at this time, based on what we know, that the most realistic “cure” for metastasized cancers that we can expect will be treating it as a chronic condition like diabetes, hypertension, etc. While falling short of remission, I think that’s something most people would be happy with if we ever get to that point.
Some lymphomas are already treated like that.
Thank you! The news I just got on the post-surgery blood workup is the reason my custom title says I’m kind of giddy.
ETA: Actually, it did say that. I forgot I changed it this morning.
Good for you.
A dear friend was diagnosed with stage 4 breast cancer last April. This is the first time her cancer was detected.
Are the odds against her being around much longer? She has a seven year old son.
