Have you heard that e-cigarettes can cause bladder cancer? No, really, they can! At least, they can if you believe all of the headlines that were going around recently about the possibility of a link between e-cigarettes and bladder cancer.
But if you dig a little bit deeper beyond just the headlines of the stories about e-cigarettes and bladder cancer—we know, we know, what a great idea!—you will find that the reports about the connection between e-cigarettes and bladder cancer are greatly exaggerated. In fact, you will find that there’s not even a real link between the two, even though vaping critics have been quick to latch onto the recent reports and cite them as yet another reason to badmouth e-cigarettes.
So what gives? What’s the truth behind the reports? Well, Dr. Konstantinos Farsalinos—who, in the interest of fairness, is a prominent pro-vaping doctor—took a closer look at the original report, which was released by the American Urological Association, and he was disappointed with what he found. Specifically, he was upset with how the AUA seems to be reaching by calling attention to a connection between e-cigarettes and bladder cancer that doesn’t even exist.
Dr. Farsalinos published a blog in mid-May and was quick to point out that the AUA findings do not come from a comprehensive study that was done. Rather, they came from a conference abstract. They also didn’t seem to measure the association that supposedly exists between e-cigarettes and bladder cancer.
But those weren’t the only issues Dr. Farsalinos had with the AUA’s report. Here are some of the other issues he brought up in his blog…
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The abstract relied on a very small sample size.
You would think that a report about how e-cigarettes could potentially cause bladder cancer would include hundreds, if not thousands, of test subjects, right? Linking e-cigarettes and bladder cancer is a pretty big deal, so surely researchers wouldn’t just test a couple dozens people and call it a day.
But it seems that’s exactly what the AUA did. In order to draw conclusions about e-cigarettes and bladder cancer, they tested the urine of 13 e-cigarette users in addition to 10 people who said they didn’t use e-cigarettes. For those who aren’t good at math, that means they only tested the urine of 23 people total before drawing their conclusions.
That is the first fatal flaw of the AUA report. Had they tested 230 people, 2,300 people, or 230,000 people and reported back on the presence of bladder cancer in e-cigarette users, it would have been a huge cause for concern. But as Dr. Farsalinos said in his blog, they only tested 23 people. That’s not a large enough sample size to make any definitive conclusions.
The abstract didn’t test for the possibility of a link between smoking and bladder cancer.
Let’s say the researchers did test more people to get a much bigger sample size. That would have made Dr. Farsalinos consider their findings more seriously. But there also would have been another issue that would have come up. That issue? The researchers conveniently left smokers out of the equation.
There’s a good chance that there could be a link between bladder cancer and smoking and vaping, as Dr. Farsalinos pointed out, which means that, if the AUA researchers wanted to prove their point, they should have included a group of smokers in their study. That group could have served as a control group for the study since there have been indications that smoking may lead to bladder cancer in the past.
But the AUA researchers chose not to include smokers for whatever reason. So even if a link existed between vaping and bladder cancer as they suggested, we would have been left to wonder if one exists between smoking and bladder cancer since the researchers didn’t take the time to analyze it. It’s another flaw in the methodology of the AUA report.
The abstract didn’t test to see if e-cigarette users were still smoking.
Before the AUA researchers started their study, they asked those in both the e-cigarette group and the non-e-cigarette group if they were smoke-free. They didn’t test any of them to see if there were any signs of smoking. Rather, they relied solely on their verbal responses.
This might be okay in some studies, but in a study like this one with a potential link to cancer on the line, shouldn’t the researchers have conducted tests to see if the participants were telling the truth about smoking in the past? If several of the participants were smokers who were just lying about not smoking, it could throw the findings off completely.
Dr. Farsalinos proposed that question in his blog and asked why the participants weren’t more diligent about testing participants for signs of smoking. It’s simple enough to test exhaled carbon monoxide to figure out whether or not someone smokes before allowing them to participate in a study. So why didn’t the researchers do it?
The abstract didn’t include important information.
This might be the biggest criticism that Dr. Farsalinos had of the abstract. The AUA researchers based the findings of their study on the levels of two cancer-causing agents called naphthylamine and toluidine. They wrote about how increased levels of these agents were found in some of the e-cigarette users.
But Dr. Farsalinos said that there was a big problem with this. He said that smokers and non-smokers often have similar levels of these two agents when tested, which means that there’s probably not any real connection between e-cigarettes and bladder cancer. Or at least, there’s not any real connection based on the AUA study.
In general, Dr. Farsalinos wrote about how he believes the AUA tried to trick people into thinking a link between e-cigarettes and bladder cancer exists, when in reality, it doesn’t seem like anything is there. But there are so many people trying to find links like these that it didn’t take long for publications to latch onto the “e-cigarettes cause bladder cancer!” headline and run with it.
Now that Dr. Farsalinos has spoken up about it, we hope that people read what he has to say and raise a skeptical eyebrow to the bladder cancer report. You can check out his blog here.