Friday, June 24, 2016

HEREDITARY CANCER

Linda and Kristen
Tucson, mid 1980s

 When Linda was diagnosed with ovarian cancer about a decade ago she was not offered genetic testing.  I believe that was because of how little was known about the genetics of ovarian cancer at the time.  Now, it is recommended that every woman be offered BRCA testing upon diagnosis, whether or not there is a family history of breast or ovarian cancer.  This is partly because treatment and prognosis in part are determined by BRCA state.  For instance, it appears certain that patients who are BRCA-positive have longer remissions.  If you have breast or ovarian cancer in your familial history you should study this web site.


(This must be a contender for the title of “most difficult web address to type accurately” in the world.  I wonder what it would look like in Arabic.)

As I have discussed elsewhere, the more OVCA and genetics are parsed, the murkier the connection becomes.  Apparently there are a dozen or so mutated genes that can contribute to ovarian cancer; BRCA1 & 2 merely have the highest “penetrance”.  (Rough definition: the higher the penetrance, the higher the probability of coming down with the disease.) 
If you study the web site you will find a pie diagram that illustrates just how difficult this whole thing of OVCA/genesis turning out to be.  The diagram shows the fraction of hereditary OVCA attributable to certain mutations – BRCA, for instance, is held responsible for ~20%.  The largest piece of the pie - fully 60% - is labeled “unexplained familial risk”.

By the way – health insurance will cover BRCA testing.

4 comments:

  1. Does Medicare cover the test? Maybe you can find out for those of us that have it. (see how I am passing on a research topic to you to keep you occupied?) Thanks in advance.

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  2. More on BRCA testing:

    http://www.onclive.com/onclive-tv/dr-robert-coleman-on-brca-testing-in-ovarian-cancer

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  3. Now here is some breaking news. (Cynicism alert!)

    https://ovariancancernewstoday.com/2017/07/10/breast-cancer-ovarian-cancer-brca1-brca2-mutations-seen-as-risk-factors-study-shows/

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  4. ACOG stands for American College of Obstetricians and Gynecologists. ACOG recently issued a list of “guidelines” for testing for ovarian and breast cancer. These guidelines apply mainly to women who carry the BRCA1 and/or BRCA2 mutations, and they seem mainly aimed at “clinicians” (doctors, not we common folk). Nevertheless, this short video is interesting and easily understood. It only takes five minutes, so give it a listen

    http://www.medscape.com/viewarticle/885927

    Whatever version of health care we end up with here in the United States, genetic testing for BRCA mutations ought to be available to all women. Do it when they’re babies. So says Dr. Myrl.

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