miércoles, 18 de mayo de 2011

Dopping and prostate. (Clembuterol and overdiagnosis)

Today I will join two of my hobbies to explain a concept that regards the two, cycling and science. The common point is the need to differentiate between two concepts: "false positives" and "overdiagnosis." It seems that we are talking about two similar technical terms, since they both are finding evidence of an abnormality, but they hide significant differences. As an example in the case of cycling can use the finding of a very, very small amount of clembuterol in the urine of Contador; in the case of the prostate we can use the presence of some subtle morphological changes in minimum samples obtained from apparently normal prostate glands of patients otherwise healthy, seen with a low magnification microscope. If it were the case of false positive doping findings, the rider actually did not submit any presence of clembuterol in urine, limiting the first findings just to a technical error in the lab that confused one substance to another. In subsequent analysis the substance would have disappeared, confirming the false positive and Contador would not have being accused of cheating. But the doping control system, as designated to prevent cheating, has suffered with severe prior cases and has tried to improve still further, prioritizing the elimination of false negative. It tends to use detection systems so perfect that they are able to discover traces of any substance in quasi molecular levels. It is intended by this that any athlete who has been in contact with any molecule of the prohibited list will be immediately accused of cheating. 

The same applies to prostate cancer risk when some healthy man, naively let the medical system look at him and gets 
positive PSA, with a great disappointment must undergo the necessary counter-analysis what in this case is a biopsy through the rectum and only if it is negative after several painful attempts will be labeled a false positive. But just as happens in the antidopping fight , the problem does not end here, frustration with the false positives, rather than celebrate the absence of the dreaded problem, tends to stimulate the search for new ways to keep discovering more cancers, by reducing quantities of PSA needed to make a positive or redefining the abnormal prostate cells suspected of being diseased. This leads to the second term I would like to explain here: overdiagnosis.
If the false positive implies its own falsity in the term himself, and it implies presumably will
have no  consequences, the athlete will left spotless and the patients will be returned to their normal lives, overdiagnosis does not leave things as they . Overdiagnosis is the diagnosis of a disease that will never lead to suffering, or evolve, or kill, but induce the label and forced to suffer the same treatment as if the disease crippling exist. Overdiagnosis in medicine arises when searching for cancer in early stages but no one really knows whether they are cancer or not, but fear tends to act as if they were. The false positive is able to uncover using a more specific test, but overdiagnosis uses tests that assigns full specificity, albeit tacit, pre-scientific, and induced to act on healthy patients as if they were risking their lives to a cancer threatening.
Overdiagnosis not only exists in medicine applied to cancer, also acts on other medicine and live  aspects, and one of them can be the fight against doping. Ultra sensitive tests can detect traces of substances, and such detection can be corroborated in other counter-analysis with the same precision, giving a sense of specificity equivalent to prostate biopsies. Everyone assigned to the prostate cancer patient who has found such a finding on biopsy, although do not feel sick, even though they do not touch if you see any tumor in the ultrasound, or scanners, even though most patients in their situation will never get sick of prostate and can get rather old, although the rate of such findings in the autopsies of healthy people is much higher than the actual presence of total real patients. The poor people suffering overdiagnosis suffer stress, operations, treatments and many tests despite being healthy. The unfortunate athlete who is found traces of any chemical substances that actually invade the air, water or food, will not be entitled to the false positive advantage
s and will suffer in their flesh wath in such a perfectionist society means the overdiagnosis capable of operating at cross healthy people and declare  cheater to top honored athletes.

domingo, 21 de noviembre de 2010

A master from Germany

Un maestro de Alemania

  Karl Popper

Martin Heidegger 

I'm reading "A master from Germany" (R. Safransky), about the biography of Heidegger and his time.
The question is where could we find the relationship between this book and the prostate, since Heidegger's philosophy concerned about being and time?...well, something does, at least i thing so, let's tray to explain.
 As the scientist that i'd like to be (although perhaps doesn't arrive farther than a mere consumer of science), I worry about I'm reading  in scientific journals. They often publish studies of questionable reliability, as evidenced by the constant presence of contrary conclusions carried out by separate teams despite its apparent respect to the scientific method. The worry even increases wen some inconsistencies become a truly fashion among the medical community, inviting us to thing in a certain way, and just a few years later every thing changes and it's supposed that we should thing the contrary.
Well, as the philosophy has a section called epistemology, in order to figure out how to get the knowledge  with a certain degree of reliability, and one of the the most lucid writers on epistemology was K. Popper, in recent years I occasionally read this author. He taught me to distinguish what is known scientifically based, from matters merely intuited and published as if they were. Interestingly I learned more of how to do a rigorous and critical study in "The open society and its enemies", where Popper analyzes the human evil hidden under the respectable Plato's old look, than in "The logic of scientific discovery". Perhaps because i prefer about Popper his rigor and honesty, witch in the second book is just explained, but in the first widely used.
Yes, Popper, I mentioned him a philosopher that I knew  while drinking wines and he told me that he worked with Heidegger 50 years ago. I spoke about Popper because it was the only philosopher remembered enough by me to keep the conversation going, and remaining able to get surprised with something interesting. The man was dedicated to ontology, as Hiedegger was, whom he hated as a person but he admired as a thinker, a paradox hard to me to understand. Because I wanted to know from long time (Heidegger), i decided to buy "A master...".
Now I'm trying to empathize with the scholastics and Heidegger's tricks to make up the puzzle whose pieces are a doctoral dissertation, a reactionary education funded by the Catholics, some pitfalls to avoid going to war and a Jewish phenomenologist called Husserl.
And once again, What's the relationship of the above mentioned to the prostate? it is very clear: making something very, very complicated, threating with illness and death and then showing the silver bullet. This is very well explained by Popper: if you know the reasons why a man develop philosopher and write, you will be able to guess what he writes before you read it, as well, if you know the reasons why some american urologist urged to investigate the healthy prostates you will be able to understand why they are still keeping on recommend, though it is useless.

Racionalism or freedom

Racionalismo o libertad.
Developments in culture, science or technology are usually associated with improvements. Because of that, i wonder the story of John Ruskin (1819-1900), which criticized the  social progress on renaissance compared to the medieval individualism. He glazed two buildings at the Piazza San Marco, in Venice, one with irregularities in each column, where every window was different from each other one due to occurrences of the worker that placed the bricks, and compared it with the newer building across, subject to the advanced architectural standards that were imposed to each worker by the architect on a regular and predictable way. According to Rusking the architecture progressed, the owner of the building was happier, and perhaps the architect too, but the Renaissance submitted the will, creativity and thus the freedom of hundreds of workers who could not finish off the bricks as they would like. Summary: the gothic beauty of improvisation were annulled and replaced by an alienating mechanicism imposed in the renaissance.
But I've being thinking till now, that the individual freedom increased progressively from the middle age to our days, being the use of reason its strongest ally. However i have to recognize that the things that made me happy were the adventure, the poetry, the music and the explosion of feelings claimed by Rusking and the romantics instead of mathematics and anatomy.
In fact, the rationalism gives us tools to survive better in the nature, but the romanticism exalt the feelings that make us happy. Study science enables us to understand how the universe works, but the paintings of Turner evokes the emotions that justify our life.
Just as science teaches us how we get sick and how we die. Just as science show us the ways to overcome the disease or replace it with the treatment side effects, the artists keep on inspiring the feelings that make easier our happiness. Is only our individual freedom which have to choice every time between the options: the chance of healing or the chance of feeling.
Facing a prostate cancer, the science propose alternatives without the pressure of others cancers that kill or heal with a big amount of certainty. In this disease, the reason fall humiliate by a virtual being that the patient doesn't  suffer with pain. Individual freedom have to wake up to decide about the own life over the social pressure. As Rusking aware that industrialization sweetened the life of a few bourgeois, at the expense of workers freedom, the social system push to consume rational medicine according to the standard pathways without considering the individual feelings.
In the case of patients with prostate cancer, a discussed and miserable cure rate is offer over some extra years of sexual enjoyment

martes, 16 de noviembre de 2010

Perplexity

Every time I attend a man who discovered an elevated PSA  by "accident", then suffered a prostate biopsy, and were shocked by the word cancer as it was written in the pathological report, once there are not chance for more delays and I must to inform him about the treatment, I wonder How will I be able to convey the advantages and disadvantages of each alternative. Resignedly, I begin my explanation like this: "you can be operate to remove the prostate, you can receive radiation therapy or you can avoid any kind of treatment." Then, i follow trying to argue that the differences, in terms of survival or at least in terms of quality of life, between the three alternatives are very low and the reliability of the studies that illustrate these small differences are also very weak.During the explanation, the reasons why i decided to become a surgeon fall collapsed. I dreamed to meet real patients with clearly effective treatments, instead of that I am faced with microscopic disease and treatments that nobody can clearly prove if improve or worse the life of anybody.

Skepticism about the cancer definition

Considering that the cancer is basically a fleshy bulk that growths, invade tissues and send metastases, how it's possible to diagnose a cancer when we only see an apparently healthy organ, without anything growing inside, with everything working well, an no metastases in the scans, only because of the findings in the biopsy?