Sunday, May 6, 2012

Personalized Cancer Diagnostics

This post is a comment to and elaboration of Dustyn's last post about sequencing the genome of a tumor. This is really interesting to think about and I think it can be looked at in many ways. We research cancer so we can discover more about what causes it, how to prevent it and how to treat it. I see this technology being beneficial mainly in the area of treatment in terms of targeted drug therapies. If it can be determined where the mutation is, drugs that directly interfere with that cancerous path can be optimal in certain cases and may be more effective than other available and prospective treatments. In the book The Emperor of All Maladies, there is a quote by Mel Greaves, Professor of Cell Biology at The Institute of Cancer Research in London who says, "It’s bad bile. It’s bad habits. It’s bad bosses. It’s bad genes.”(1)
Cancer is a disease with an array of causes, so even if one's DNA sequence shows where the mutations is, there are still a whole host of potential reasons for its presence. That leads to many more experiments to be done regarding prevention and treatment of cancer and then us back to asking if the technology was valuable. If the mutation can be determined, treatment would perhaps be more efficient but I do not necessarily think that would always be the case. We treat many diseases today where we have no idea what the cause is, yet we know certain treatments work. Sidney Farber said, “…nor is it necessary, in order to make great progress in the cure of cancer, for us to have the full solution of all the problems of basic research…the history of Medicine is replete with examples of cures obtained for years, decades, and even centuries before the mechanism of action was understood for these cures.”(1) Is it worth our time to invest in this technology instead of in areas such as discovery of treatments or will this help us in make progress in treatment? Studies would have to be done to show that this technology leads to an overall more positive outcome for patients.

Another concern is that it takes 24 days to get the results, and I would imagine more time would be needed to analyze the results and then determine courses of treatment. With that being said, I assume the patient would undergo some sort of treatment in the meantime since time is so critical. By then, the question, ‘Is it worth it?’ arises again.

As for the pricing, it is a costly technology that many people would be unable to afford. Would insurance cover it? If not, it definitely poses an ethical concern and gives wealthier people the upper hand in terms of survival (if the technology proves to be valuable). Also, if the individual is paying to have the genome of their tumor sequenced, it is most likely for their own benefit and probably in hopes that it will aid in better treatment and thus a better survival outcome. Therefore, at the time, determining the cause and how to prevent the cancer may not be as important to the individual, although it definitely still plays a role. I say this because I wonder if the information from certain individuals would be strictly private information or if it could then be placed in some sort of database for others to access. This database could provide the type of tumor, location of the mutation(s), treatments used, and survival outcomes. Certain mutations may correlate to higher death rates, which can be used to help determine prognosis and the best courses of treatment. However, this then leads to what you were saying about a patient becoming depressed because they discover they have a mutation that correlates to a very poor prognosis. I have found a lot of scholarly articles related to depression in cancer patients but it is a complex issue and is influenced by a lot of factors. It is difficult to study because it relates to a patients genetic makeup, social environment, stage of disease, level of pain, and many other factors. In general, I did find that depression puts cancer patients at a greater risk of death.(2) Overall, it is hard to say if the benefits of this technology would outweigh the costs. I think it is also difficult to determine whether or not it will have an impact on depression in patients but I think if the technology is used strictly to determine a cancerous mutation, it would not have a significant impact on depression levels. This is because hearing ones prognosis is something all cancer patients inevitably face and I do not think this technology will be an important tool in gauging prognosis. If anything, it could potentially lower depression levels because if the exact mutation is known, it could lead to more effective and more promising treatment.

Do you think it would be ethical to publish results (without patient names) from genome sequencing if this technology became available? If so, would it contribute to our knowledge of cancer and aid in treatment and prevention?