The roots of cancer

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Added: Wed Nov 28th 1:49pm
Posted in: Cancer

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Cancer does not "just happen".  Cancer along with many other common diseases is not just a chance occurrence.  There is a growing and unequivocal body of evidence supporting the concept that most common diseases are the result of complex interactions between a persons basic genetic heritage and multiple environmental factors.  Over time it will be our goal to examine these [biological/environmental] relationships and make them better understood.  More importantly I want to create opportunities for personal action to reduce the risk of experiencing one of the common diseases.  If you already have one it is never too late to explore ways to improve your odds of surviving and living life to its fullest potential.  Cancer is many diseases but in general the genomic revolution in health care bears a high degree of clinical relevance to cancer because it influences everything about cancer. From risk or disposition [personal and family], diagnosis, tumor biology assessment, treatment strategies and planning, prognosis assessment to survivor management genetics are playing an ever growing role.  In addition genetics is a powerful force in cancer research and has given birth to the concept of "targeted research" which allows medical science to pinpoint very specific areas for investigation.  Such investigations can produce dramatic results in much shorter periods of time leading to rapid availability of new therapies.  We will discuss one of these exciting developments another time soon.   Oncology [the medical specialty of cancer care] with the help of cancer genetics is establishing a new paradigm in cancer management spanning many interrelated disciplines.  Cancer risk or disposition is influenced by several different types of genetic mutations.  It is most dramatically affected by the presence of what we call "dominant mutations" in the human genome [all the genes in a persons body].  These gene abnormalities are typically inherited from ancestors who pass them on through the germ cells in the body [sperm and egg] that create new life. It is estimated that these inherited mutations may account for 5 - 10 % of cancers.  Because these mutations are widespread through a persons body [effectively in all tissues] they can and do significantly increase the risk of cancer in more than one location.  A good example is a mutation known as "BRCA 1" on chromosome # 17 which predisposes to breast and ovarian cancer.  This risk can be as high as nearly 100%.  There are many other "dominant mutations" that can be inherited affecting colon cancer and melanoma among others. There are also many weaker changes [mutations] in our genes known as "SNPs" or "polymorphisms" [a fancy medical word that means structural change in a tiny area of the genes].  These lessor but inheritable mutations may be involved in as much as 20 - 30% of cancer cases.  It is worth noting here that the human genome is made up of approximately 30,000 genes.  These genetic "polymorphisms" individually may not be too troublesome [remember their effect is limited] but some people have a lot of them and they can gang up on that person and increase their cancer risk.  We are just now seeing the advent of testing for these polymorphisms.  A group I have worked with for years [Intergenetics] is in the final phase of an FDA study that will lead to the first genetic screening test for breast cancer in the "average woman" [someone who has no family history or other known risk factors for cancer].  This test is known as OncoVue and is done on a simple saliva specimen that contains cells from the cheek area.  It is important to realize that 80 + % of cancer arises in people with no obvious risk factors for the disease so this type of testing could play a big part in how we take care of "average risk" patients in the future.  It will in fact enable us to practice true personalized health care.  Other specific cancer risk tests will be forthcoming over the next decade.  By knowing a persons genetic status, special and intensified cancer screening programs can be tailored for these people at greatly increased risk.  In addition other interventions can be offered ranging form lifestyle/nutrition changes, medical [chemo - prevention] to prophylactic surgical procedures.  All of this can either prevent cancer from being established or provide for an early diagnosis where the hope of cure can be 95%. You can get the cancer prevention ball rolling in your own life by carefully looking in to your own family history.  We will discuss this and much more in our next chat.  Until then enjoy each and every day.