Your body is incredibly good at repairing itself.

A skinned knee quickly fades to just a memory. And if you give that runny  nose a few days of rest, you’ll be able to breathe  through it again in no time.

But one big problem that your  body often can’t fix is cancer. Without treatment, cancer will keep growing nd spreading until it kills you. Thankfully, we have many treatments -- chemotherapy and other treatments  that have saved millions of lives.

These therapies are pretty much your  only option for surviving deadly cancers. However, there are a few cases where  something truly remarkable happens. Doctors have reported some rare  instances of tumors shrinking or even disappearing without treatment.

Getting to the root of this medical marvel could help more cancer patients in the future. That is, if we ever figure  out what the heck is going on. So here’s what we know  about spontaneous remission. [intro music] The idea that cancer might heal all by itself has been around for a long time.

The first mention of cancer  pulling a vanishing act shows up in the Ebers papyrus around 1550 BCE. And perhaps the most famous historical  example dates back to the 13th century. As the story goes, an Italian  priest called Peregrine Laziosi had a tumor in his leg that required amputation.

But his tumor miraculously  disappeared before his surgery. This miracle earned him the title  of patron saint of cancer patients. Then, in 1813, the French  physician Arsène-Hippolyte Vautier claimed that tumors in cancer  patients who were sick with gangrene sometimes mysteriously shrunk.

Around the same time, other physicians also wrote reports about patients with incurable cancers who miraculously recover after becoming ill with some other disease. This is not a whole lot to go off of. But medical reports from the last 200 years do seem to confirm that cancers  sometimes shrink or go away without treatment.

To be crystal clear, I’m not  saying that this happens often. Cancer patients should not  bank on spontaneous remission as a solution to their life-threatening diagnosis. These cases are exceedingly rare.

A generous estimate puts  spontaneous remission happening in only one in 60,000 cancer patients. And since it’s cancer, even  cases of spontaneous remission have been known to be just a temporary respite, with cancer coming back  after a few months or years. So if your doctor recommends a cancer therapy, that’s still your best bet.

Listen to your doctor. They’ll probably tell you  it’s still not really clear why some cancers go away like this. That said, scientists have  picked up on a few trends.

For one thing, some types  of cancers are more likely to exhibit spontaneous remission than others. Take neuroblastoma, a nerve cancer that mostly impacts  kids under the age of five. One study from Denmark found that up to 2% of Danish neuroblastoma patients  experienced spontaneous remission.

Other cancers that occasionally  go away by themselves include kidney cancer, metastatic  skin cancer, and leukemia. But when I say “occasionally,” I mean not often. As of 2013, there were only  76 well-documented cases of spontaneous remission in  late-stage skin cancer. … n the world.

And that included all reports dating back to 1866. In all of that time, scientists have  only started to build an understanding of what’s behind spontaneous remission. Insufficient data really slows research down.

But one thing they’ve noticed is that  people who experience spontaneous remission have sometimes been exposed to tiny intruders. Nasty viral and bacterial stuff. In 2023, doctors reported 14  cases of spontaneous remission in cancer patients who had caught COVID-19.

Although! If you have cancer, don’t try to get COVID in the hopes  that your cancer will go away. Cancer almost always increases  your odds of dying from COVID.

There are safer ways to test this connection. Like in 1978, a 78-year-old man with leukemia who received the smallpox vaccine went into total remission. In another more recent case, a patient recovered from skin cancer  after getting the Tdap vaccine.

So the link between infections  and spontaneous cancer remission has been seen multiple times over the years. And researchers are trying to figure out why. But before we explore their various  hypotheses, it’s time for a quick ad.

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Scientists have suggested that infections might help the immune system  identify cancer as a problem. Sometimes, anti-tumor  treatments trigger the release of a bunch of tumor-related  markers called antigens. When your immune cells  recognize these tumor antigens, they might be able to find  and attack the cancer cells.

That’s a possibility. But it doesn’t explain all  cases of spontaneous remission. Sometimes, spontaneous remission  happens without any sign of infection.

Like when doctors witnessed  spontaneous remission occur after biopsies or other routine medical screening. It could be that surgery or biopsies make  it harder for cancer cells to get blood. And, like vampires, cancer cells  need a lot of blood to get by.

So these interruptions might just  starve cancer cells to death. There might even be a genetic reason for the mysterious disappearance of cancer. While the case is definitely not closed, the search for answers has led  us down really helpful paths.

Like life-saving cancer therapies  dating back to ancient Egypt. An Egyptian physician named Imhotepno, not that guy, different guy, suggested treating cancer patients by making a precise incision near the tumor, where an infection could brew. Later, an American doctor  worked off the same concept, using bacteria to treat cancer directly.

In 1890, William Coley, started injecting inactivated  bacteria into patients with inoperable skin and bone cancers. Their prognoses were …not good. But after his unconventional treatment, around 52% of his patients went  into remission for five years, and another 20% were still alive  20 years after their injections.

The ‘Coley Toxin,’ as it was called, was used to treat this type of cancer until 1963. But concerns about injecting  people full of bacteria made some doctors skeptical about the treatment. Then there was the issue that to this day no one fully knows why Coley’s Toxin works.

So, when chemotherapy and  radiotherapy came around, many doctors opted to use that instead. But even today, researchers are  still working on viral mechanisms to make your cancer go away. The FDA has approved a therapy called T-Vec that uses a modified virus to  essentially blow up cancer cells.

Though, if you go on the drug’s website, there’s a little asterix on this description where the drug company admits they don’t  actually know how the virus does that. Still, this kind of medication could give  hope to people with tough-to-treat cancers, thanks to ancient cancer medicine. Cancer remains one of the leading  causes of death worldwide.

Even at the height of the  COVID-19 pandemic in 2020, it was still responsible for  around one in every six deaths. I think, obviously, The extremely rare instances  of spontaneous remission don’t mean you can shut your  eyes and reject treatment. Odds are, your cancer won’t be one  of those cases that just disappears.

But with some research and a little luck, this phenomenon might lead to more treatments that help more cancer patients in the long run. And remember, I know I talk very confidentally but I am definitely not your doctor. So talk to them for any actual conversations  about actual treatment plans [ OUTRO MUSIC ]