Guess what? Chemotherapy can CAUSE cancer...

In a shocking (or not so shocking) continuation in the trend of “what’s good for us one minute is absolutely terrible the next” in medical science; we’re finding out now that chemo, the standard treatment for cancer, can actually cause cancer in some patients.

I’m gonna go buy a pack of Newports and toast my super-size Slurpee to good health.

Not big news. Pretty much any basic oncology text will tell you that.

Well this is the first I’ve heard of it and apparently it was news to the researchers in the study highlighted in the link, as well as being mentioned today on NPR, why do you think that is?

From the article, it isn’t so much that the chemotherapy causes cells to become cancerous; rather, it causes normal cells to make a protein that simulates cancer cells (in the tumor being treated for) to grow. However, it has been known for a long time that many of the substances used in chemotherapy are carcinogenic in themselves

Some of the examples on that page are listed as being known carcinogens since the 1980s, yet they are still used, because the benefit is seen to outweigh the risk (being a carcinogen doesn’t mean that cancer will occur with exposure but the risk will increase with exposure; for example, the risk of acute myeloid leukemia from taking cyclophosphamide can be up to 1-2% at high doses over the next 9 years, before dropping to normal levels, so there isn’t a lifetime increased risk of cancer).

Radiation causes cancer, yet radiation is a standard cancer treatment. What makes this news?

Even if there’s a 50/50 chance split between a cure and making the cancer worse, that’s better than a certain death sentence.

Another vote for this not being news, except maybe in its specific details. The basic idea of chemotherapy is that it’s poison, The idea is that the damage caused by the poison will be less than the damage caused by the cancer. But sometimes it’s a thin line. There are certainly patients who have died from chemotherapy.

In all honesty, why was this news? :confused: I heard about this study from numerous news-media sources, and they all treated it as breaking medical news. I didn’t go searching for this story, it was in many places.

I don’t know, but there’s a commercial right now where a race car driver is auctioning his car to help the kid, who was treated for leukemia, get help for the skin cancer caused by the leukemia treatment, so…maybe that’s just making some people go ‘Wha…?’

Reports about health threats draws in viewers.

It is news because the mechanism of action has been identified, so researchers have a new target to look at to prevent chemotherapy resistance.

Oncologists knew about chemotherapy resistance, they just did not know how or why. Now they have more information, they can choose better drugs, or develop new drugs that suppress the resistance response.


You might find the book The Emperor of All Maladies: A Biography of Cancer interesting reading. It’s written for the general public. I was surprised to read that there are chemotherapy drugs which were first used in the 1950s and are still the standard of care today.

As they say, the goal of chemotherapy is to kill the cancer just ever so slightly faster than you’re killing the patient.

Also, it’s been known for years that many tumors actually secrete substances that suppress the growth of cancerous tumors elsewhere in the body, so often secondary tumors begin to grow shortly after the primary tumor is removed.

Most cancer treatments can cause new cancers down the line, because they kill the tumors by damaging DNA. As a side effect, they cause DNA damage to other healthy cells as well. Its a cost-benefit thing - cure it now, and deal with the consequences 10, 20, 30 or 40 years down the road.

I was treated for lymphoma at 17. The way I was treated (radiation) has increased my chances of developing solid tissue tumors over ten-fold (I’m hoping that if/when the time comes, treatment therapies will have advanced far enough to deal with it.) and they took out my spleen for really no good reason other than it was what they did at the time.*

If they didn’t treat me, I would have died. If they did treat, I had a 90% chance of a cure, with issues to be aware of some decades down the road. A no brainer to me.

*They don’t use radiation for the stage of cancer I had anymore - they have better chemo drugs these days, and routine spenectomies with no presenting pathology are not performed anymore.

Chemotherapy is not the standard treatment for all cancers. Everybody who has had chemotherapy has been told that it can cause cancer. The news here is more specific.

Developments in cancer are always news, and so are health stories that sound counterintuitive.

I certainly didn’t know that, and I’ve had 3 close relatives with cancer. I knew chemotherapy is essentially poison, but didn’t know it was also a carcinogen.

From what I understand, X-Rays and CT scans can cause cancer, so you just can’t win. Just going through one of those test could be considered a calculated risk. I also hear bad things about MRI contrast dye.

The whole thing is scary and frustrating. While the doctors are trying to figure out what’s wrong with you and fix it, what other damage is being done? Don’t even get me started on prescription drugs and their minor to major side effects.

The best thing to do is stay healthy and stay out of the hospital, but there’s always the chance you’ll still get a disease even if you do everything “right” to the best of your knowledge.

Why do I suspect that there will be some ‘new’ chemotherapy drug to hit the markets in the next 3 months that ‘fixes’ the problem identified in this report?

I don’t know why you suspect that, because there is no basis to make such a claim. :rolleyes:

A group of independent (i.e. not from a pharmaceutical company) researchers have identified a particular protein produced by fibroblasts that encapsulate tumours that is increased by chemotherapy. This protein triggers additional tumour growth. This is pure research, and published for everyone to see. It may help develop new therapies.

Now, groups all over the world will be examining this protein. Some will try to identify the cellular pathways in tumours that this protein targets to produce inhibitors. Some will try to block/deactivate the protein itself. Some will work on fibroblasts to limit the DNA damage or block WNT16B. It will take years and millions of dollars to identify any working therapies, and much of that time and money will be spent to find out what does not work.

Then, once a therapy has been identified, it will take another 5 years of clinical trials and many more millions to get the product to market and into production.

So, not three months. Not even three years. But this is good news.

Look, I don’t like the marketing arms of Pharmaceuticals - they can be aggressive and pushy and have dodgy ethics. But …

those companies pay for the research into the drugs that save lives all over the world. They are embracing concerns about access to drugs in the third world. There would be no antivirals, no antibiotics for TB, no vaccines to wipe out smallpox, polio, no antimalarials. No Avastin, Tamoxifen, chemotherapy. Without the Pharmaceuticals, many, many people would die every day all over the world.

Si (who relies on antivirals from Gilead every day)

Of course it’s a calculated risk. That’s why you wear a lead bib on the body parts you don’t want scanned, the scans are done as rarely as possible, and the X-Ray tech leaves the room before pushing the button. These things have dangerous properties but the risk of getting cancer from an X-Ray or something similar is small, and if you have a problem you need diagnosed, it’s worth taking a small risk. When you’re in a more desperate situation, the risks of chemotherapy or radiation may become worthwhile.

That’s right. The real risk is in cumulative exposure.

Interesting. Does anyone here know if these substances have been investigated for potential therapeutic use?