Bad Science: Fated to Get Cancer?

There was a recent article that came out of Cancer Research UK, a charity dedicated to raising awareness about cancer prevention titled "More than a quarter of Britons think cancer is a matter of fate," which was then reported on by Agence France-Presse in a reported titled "Cancer is Due to 'Fate'; Britons believe." Each of these publications describes the findings of a survey asking a cross-section of the population if they believe that "they could do anything to reduce their risk of cancer or whether getting the disease was just fate." Overall, they report, 23% of the population believe it is a matter of fate and that their lifestyle choices did not play a role in determining whether or not they get cancer.

I noticed that this story has gotten picked up by a number of members of the medical-science blogosphere and it seems as though there are a number of differing opinions about the interpretation of this study. If there is confusion amongst us, then I'm certain that there is even more confusion among the general public about what exactly this all means. Here, I would like to offer some of my own thoughts on the matter and how it illustrates a number of key points that I often see arising in the field and how it can lead to disagreement.

1) Source: Before we even get to the results of the survey, and even before we make conclusions, we have to examine the source of the information. As a charity driven by donations from people concerned about cancer, I doubt that Cancer Research UK is an unbiased arbiter in the information collection business. I am not surprised that the survey they conduct results in data that supports the need for their own organization. This is why polling services are used by a majority of interests groups, so that they can not be blamed for influencing the results.
Moreover, the original source is a press release and the coverage is based upon the scant information provided in it. This brings up two important faults: a) we do not have access to the original data and methods (see below) and that there was no oversight in the way the survey was conducted (no peer-review) and b) the information has been processed by two people who probably have very little experience in reporting scientific results. I don't know about you, but most of the humanities majors I knew in college loathed their science work [the rant on teaching science in college will be saved for a later time] and would probably have a hard time fairly making conclusions about a report that has an unclear experimental method (again, see below).


2) Experimental Design: What was the exact question posed to Brits in this study? We don't have this information. The wording of such surveys is extremely important, especially when the wording can influence the responses of the participants. Without the wording, we can not know for sure if this report was clear and unbiased. For this and the reasons above, I usually don't read these kinds of report expecting to learn something.

3) Results are open to interpretation: In perhaps my biggest gripe about this report, I feel that the results, as described, are ambiguous. For this, I will draw on a hypothetical example, illustrated below:

In this scenario, we have a total population of 200 people. We assume that the occurrence of spontaneous cancer is low, about 1%. Splitting the groups into smokers (ie lifestyle choice) and non-smokers of 100 each, we would expect that 1 person from each group would get cancer, regardless of any lifestyle choices. We can say that fate was not on their side because there was nothing they could do.

Assuming that smoking raises your risk 10 times, we then would expect 10 out of 100 smokers to develop cancer for a total of 11.

This is where the results become a point of debate. What makes the 1 person in the non-smoking group get cancer - is it fate? In this case, lets assume yes. The difference between her and the 99 other non-smokers was simply a stroke of bad luck. And the 1 smoker who gets cancer who would have gotten cancer anyway? Again, lets say that fate was responsible. Then there are the 10 additional people who got cancer in the smoking group. What made these 10+1 people instead of the other 89 "healthy" smokers is unclear and attributed to chance, or fate* in this case.

As other bloggers correctly indicate, no physician can tell a patient with certainty whether they will get cancer, smoking or not. In fact and to be fair, there is a greater chance that a smoker will not develop cancer (89) than actually get it (11). Making the assumptions above, it is fate that separates the 1 from the 99 in the non-smokers and the 11 from the 89 in the smokers group. Looking at it from this angle, it is valid to claim that fate is responsible for who gets cancer and who doesn't.

But to say that it is fate that dictates the 10 smoking-caused cancers vs. the 1 spontaneous tumor in either group is simply not true. It is the lifestyle choice itself that has given rise to the 10 additional malignancies. Therefore, we can no longer state that fate alone is responsible for cancer, irrespective of behavior.

Conclusion:
These kinds of studies may lead to confusing results. We can go back and forth on this all day depending on our interpretation, but ultimately it is the experiment and conclusions drawn are flawed from the get-go. We need to be cautious of our source of information and not let these press releases do more damage than good when their results are not scientifically sound.

* A note on "fate": Simply because something is unknown, does not mean it is due to fate or chance. There are many phenomena that we do not quite understand completely and tumorigenesis is one of them. Many things that used to be considered fate or luck now have scientific explanations. Take, for instance, the people who can have repeated unprotected sexual intercourse with an HIV+ partner without acquiring the virus (akin to not developing cancer despite smoking). An uninformed observer would say that these people are not fated to get AIDS. However, in reality, these many of these people are descendants from survivors of the Bubonic Plague in Europe. The disease selected for a genetic polymorphism that made some people resistant to viral infection and this allele remains today. I suspect that the susceptibility of some people (the 10) over others (the 89) will soon become clear in time with a biologic rational rather than pure fate.

Reference List of Words

MudPhud - Shorthand/slang term for person holding both MD and PhD degrees. Also, MudFud.
MSTP - Medical Scientist Training Program; NIH-funded dual degree (MD/PhD) program.
Pre-Med - Person who aspires to enter into medical school.
PI - Abbreviation for Principal Investigator.
Principal Investigator - usually the head of a lab who directs the research
SDN - Student Doctor Network (excellent resource for medical school information).

Note: this post will continue to be edited as I go along and I feel the need to add terms.

Difference between MD and PhD

I found this good, although not entirely accurate post, over on the SDN forums.

By ScottishChap
M.D. - harder to get into, easier to get through, science classes just scratch the surface, can get by by memorizing like a parrot, not treated as a colleague, expensive, independent thought is dangerous, program lasts 4 years, instructors can't mess with the class mean without repercussions, students whine a lot more, students assume all Ph.D. students are unhappy med school rejects. Overall: subject matter is one inch deep and 10 miles wide.

Ph.D. - easier to get into, harder to get through, science classes take it as deep as current knowledge permits, will fail if all you do is memorize, treated more as a colleague, inexpensive, independent thought is rewarded, program lasts 3-7 years, instructors can make exams hard enough that the mean is 40% without repercussions, students whine much less, students assume all M.D. students are snooty and arrogant. Overall: subject matter is 10 miles deep and one inch wide.

Now, where does that leave us MD/PhDs??

Getting Scooped

Success in academic medicine is largely measured by publications. In fact, we live by the code: Publish or Perish. This means that you either show your abilities in research by publishing articles in peer-reviewed journals or else you will be deemed unproductive, incompetent, and ultimately irrelevant in the eyes of your colleagues.

There is TREMENDOUS pressure to publish. Not only are you concerned that about showing some productivity (it can be years between publications), but you will also be intimately worried about the possibility of someone beating you to the punch and publishing the same findings first. Researchers call this "getting scooped." This is bad news because it means your research project has just gone from being cutting-edge to yesterday's news. Novelty is lost and it looks like the other guys thought of it first (regardless if you did or not), so they can then claim all the credit.

It may seem uncommon, given the immensity of science, that two or more groups would be working on the exact same research project at the exact same time. Heck, it might even seem counterproductive for research dollars to be spent investigating the same thing. [Note: I'll save the debate about competition in science for another post.] However, it actually happens all the time. Just think of Elisha Gray. Who is Elisha Gray? Exactly. He's the guy that got scooped by Alexander Graham Bell in inventing the telephone. Bell made it to the patent office only a few hours before Gray. Point of the story: Don't be like Gray, don't get scooped. Of course, this means living in perpetual fear whenever you start a project because you are worried about whether someone will have already started on it and thus have a head start on you. Or, there are always those people out there who work day and night, sacrificing body and soul, in pursuit of scooping other people (aka Gunners).

Although most academians claim to be collegial, I know few who are entirely open with their ideas and data, simply because of the possibility of being scooped. There will always be the eager grad student/post-doc/PI sniffing around for the latest great idea to steal and publish without recognizing the origin (unless of course she praises himself for her ingenuity). As an aspiring researcher, you should be mindful of this fact because you don't want to share more information than you want to, but you still want to maintain collaborations. I'll admit its a tricky balancing act that will take some time to learn and you'll probably get burned a few times before you know when to pipe-up.