Hey y’all.
My dad was diagnosed with stage four non-small cell lung cancer back in February. It’s been a tough few months. He had three rounds of chemo and then they did a follow-up scan last week. They told us that he had a mixed reaction to the chemo. While it seemed to shrink the tumors that were initially giving him pain (yay less pain!), it seems some smaller tumors appeared/grew a little bit (between 0.3 to 0.5 centimeters, not yay).
Can anyone explain to me in simple terms why this occurs, or direct me to online resource to explain why that occurs? Why chemotherapy shrinks some tumors but not others/doesn’t keep it from spreading?
Thank you.
In: Biology
Chemo is rough sorry for you and family. It is designed to stop cell division. This is why it’s used to treat cancer. Cells go through phases when dividing. Chemo is designed to attack during certain phases. So if not all the cells are at the same phase at the same time it may be more effective on some tumors and less on others. Unfortunately chemo doesn’t discriminate very well between cancer and non cancer cells. It effects non cancer cells as well, This is why chemo patients frequently get sick days to weeks after treatment and why they can’t just go crazy slamming a ton of chemo into someone. It is very hard to stop spread after stage 4. At this point cells have broken loose and travel around the body and can grow anywhere though there are typically a few common places such as the liver and brain that seem to be affected more than others. Picture a dandelion. you blow all the white fluffy seeds they’re carried by the wind and wherever they land a new dandelion can sprout up. Imagine trying to find ALL the tiny seeds in a lawn, darn near impossible. Just like finding every cancerous cell in a human body.
So… my mom was diagnosed with stage 3 small cell lung carcinoma in February too. Believe me I know it sucks.
I’ll also preface everything here with “I’m not a doctor, but…” – because I’ve done *tons* of research and digging around, just to be as “educated” as I can be about the whole situation. I would *heavily* encourage you to do the same, for your own satisfaction and making some amount of logical/rational sense from it all. I entirely “get” what you’re going through, it sucks, and my heart goes out to you as some random internet stranger, going through basically the same thing.
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With all that said, from what I’ve looked up and into, sat through consultations and checkups, scans and dozens of questions…
Chemotherapy finds it’s origins linked back to mustard gas. Mustard gas was a poisonous gas used in WW1. But *somewhat* similar to alcohol; and how it’s a poison, but people drink it “for fun”, we can still find useful purpose to a poison like mustard gas. This is ***NOT*** to say that they’re injecting your dad with mustard gas, chemistry and drugs have come a long way since WW1; just explaining that “aspect” of it.
Chemotherapy drugs, ***typically*** operate on the same overall effect. To slow/stop ***any/all*** cells from growing/reproducing. Cells that reproduce/grow quickly, fall under this umbrella – and that definitely includes cancer cells. But it also includes a lot of other “normal” cells in the body – like hair follicles; it’s why cancer patients lose their hair, because hair follicles try to grow new hair so quickly and with such a drug in the system stops them from reproducing anything, their hair falls out. This extends to any/all cells that reproduce/grow quickly too – skin cells, reproductive cells, red & white blood cells…
Chemotherapy isn’t really doing much to actually “kill” the cancer; it’s just stopping it from growing. It lets the existing immune system – even if that immune system is taxed from the chemo itself – to deal with the tumor.
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Now, my mom was diagnosed with stage 3 cancer, and your dad with stage 4 cancer.
There’s some *very loose* analogy here, that chemo is like carpet-bombing an island (the body) to deal with a mouse (the cancer).
When that cancer would be caught early, then the mouse wouldn’t have more than a couple burrows and barely tunneled through anywhere. When that cancer is caught late, like stage 3 & 4, then the mouse is, or should be assumed to have other burrows & tunnels around.
I’m going to assume your dad had other, previous scans that didn’t show much of anything; but then almost out of no where he’s got a large tumor that they diagnosed as stage 4 cancer. ***Chances are*** here, that the cancer, like that mouse, had other tiny (0.05cm-0.1cm) clusters, that ***ANY*** scan couldn’t really detect; or could just as easily be confused for generic static or otherwise unimportant fuzz in the scan.
That then means that, by the time he actually got the chemo, those other “branches” of the cancer would be slowed/stopped – and perhaps the “main” tumor is shrinking, but the other “micro-tumors” already existed, and are slowed/stopped.
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Now you’re also kind of fuzzy with defining the treatment plan…
My mom has gone through 4 cycles, and only 4 cycles, of chemo. There was about 2 weeks between each cycle. And each individual cycle was 3 consecutive days of “we’re gonna inject you with stuff”. With nurses & doctors confirming that *most* patients go through 6 cycles instead of 4, I don’t know why my mom only went through 4 instead.
You said your dad just finished “3 rounds of chemo”, but that’s kind of ambiguous with where along the whole treatment plan that is, with what I’m familiar with. Like, 3 rounds of chemo, relative to my mom’s case, would only mean it was the 1st “cycle” and she’d still have several more cycles to go. Or if you’re talking “rounds” meaning cycles, then that would still be anywhere between 1/2 to 3/4 through the whole “chemo plan” – your dad isn’t done yet; and there will likely be more scans to see how he’s reacting and how the tumor(s) are reacting.
With the *additional* aspect that none of chemo involves radiation therapy. Radiation therapy is more like, pointing lasers at them, at specific parts of the body, to try to aim it directly at the tumor and poke holes in it/kill it enough for the immune system to deal with it. Radiation therapy as I’ve seen, is more often “every single day, for 6-ish weeks” as opposed to chemo, which has been 3 days every 2 weeks, for 4-6 cycles, kind of thing.
If chemotherapy is like carpet-bombing an island to deal with a mouse, then radiation therapy is more like using a shotgun at 100ft to deal with the mouse.
Think about cancer the same way you might think about a bacterial infection. The cancer is kind of it’s own organism, and can mutate seperately from the human it’s infecting. The ability to mutate quickly is what makes cancer, cancer.
When you go through chemo, you’re using a specific drug or cocktail of drugs with a specific mechanism. Some of those cancerous cells are going to either A. Be innately resistant to that drug or B. Develop resistance to that drug.
As an example, docetaxel is a common chemo drug. It works by binding to something called tubulin, which is the protein that acts as a scaffold inside cells. It’s really important that tubulin is able to break down and move around if the cell wants to divide. Docetaxel glues all the tubulin together.
A cancer can develop docetaxel resistance in a few ways.
* Mutations that change the site on the tubulin where docetaxel binds, so it can’t any more.
* Mutations in things that depend on tubulin such that they can work without it
* Increased amounts of cellular pumps that can spit out docetaxel from the cell
Lots of other drugs follow that same sort of pattern – either change the target of the drug, change the cell’s mechanisms around the target, or just do some things so the drug can’t get in, or gets spat out.
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