Breast Cancer: Having The Gene Is Not Destiny

angelina-jolie-mastectomy.jpeg3-1280x960The recent news about Angelina Jolie and her bilateral prophylactic mastectomy has brought renewed attention to the high risk of women with BRCA gene mutations of both breast and ovarian cancer.

I would agree that Jolie’s decision to undergo surgery was a reasonable choice. It is well documented that bilateral mastectomy is one of the most effective ways to limit the risk of and mortality from breast cancer in women with a BRCA gene mutation, particularly when performed before the age of forty.

However, that’s not all there is to it. While family history can be an important indicator of breast cancer risk, there’s a critical point that often gets overlooked. Jolie’s situation and its extensive coverage have presented a tremendous opportunity for the medical establishment and Jolie to address a commonly held misconception that has potentially dangerous consequences – that the leading risk factor for breast cancer is a gene mutation resulting in a hereditary predisposition to cancer.

This, in part, reflects confusion about the difference between “hereditary” and “genetics,” with regard to cancer risk. Hereditary risk factors are changes in the genes you inherit from one or both of your parents, which are present in all cells in your body. In families with a very high cancer risk, some family member(s) might inherit that abnormal gene. It is important to note that while virtually all cancers are “genetic” (resulting from changes in specific genes), most cancers are not inherited but, rather, reflect the genetic changes that occur within the DNA of that cell. Over a period of years, a mutated cell can give rise to generations of new cells that acquire additional genetic changes, eventually resulting in an actual cancer. Thus, strictly speaking, all cancer is “genetic” but not necessarily inherited.

I coauthored a 2006 study in Connecticut conducted by Environment and Human Health, Inc, surveying a large sample of women without a cancer history that assessed their understanding of breast cancer risk. The results reaffirmed how frequently the public misunderstands and overestimates the role genetics and family history play in breast cancer risk, with one quarter of the women believing that 75% of all breast cancers are caused by inherited gene mutations such as BRCA-1 or 2.

What we do know is that only 15% of breast cancer in the US is related to a strong family history, and only 8-10% of breast cancer has a defined inherited genetic predisposition.

On the other hand, if a woman does have a high risk BRCA-1 gene mutation, she has an 85-95% risk up until age 70 of getting breast cancer and a tendency toward earlier onset of both breast and ovarian cancer.

The problem is that women are confusing the high risk in individuals that have the gene mutation with the general risk of getting breast cancer. What are the consequences of this misunderstanding? That many women without a family history or genetic predisposition to breast cancer are underestimating their actual risk of getting breast cancer and are not taking adequate preventative measures, like screening. I even hear “I don’t have a family history, so I don’t have to worry” from my own patients.

A critical piece of the puzzle is the strong environmental component that has led to in the dramatic growth in the incidence of breast cancer in all women. Many of these environmental factors are known, including reproductive history, hormonal factors, diet, and lifestyle. But something has also changed in the last 40+ years that appears to have increased the lifetime breast cancer risk in carriers of an inherited BRCA-1 or 2 gene mutation from 20% up to 85%-95% risk, similar to the marked increase in non-inherited breast cancer incidence over this same period. Unfortunately, this is rarely talked about. And this cannot be due to an increase in the frequency of these genetic mutations, because it would take hundreds-to-thousands of years for this magnitude of change to occur.

Despite all the media coverage, public awareness campaigns, and money spent on disseminating information on breast cancer, this critical issue continues to be misunderstood.

Despite the evidence of high risk that women with these mutations face, having the gene is not destiny.

Beyond the aggressive surgical approaches currently being employed, there is a critical need to determine what specific environmental factors are responsible for the dramatic increase in breast cancer. 

The ultimate goal must be to seek the safest strategy to prevent this disease in all women.

In my next blog post, I will discuss the potential role in environmental factors in raising the risk of women carrying the gene. In the interim, I invite you to ‘like’ my Facebook page, follow me on Twitter, join my LinkedIn network, and please visit my website, www.drbarryboyd.com

14 thoughts on “Breast Cancer: Having The Gene Is Not Destiny

  1. Natalie Palmer

    Hello Dr. Boyd,
    I enjoyed reading your post and found it very informative. You answered a lot of questions people have been asking since Angelina came forward with her story. May I reprint your blog on our website?
    You can take a look at our site here: http://www.thepinkpaper.com

    I look forward to hearing from you.
    All the best,
    Natalie Palmer
    Co founder / Editor
    The Pink Paper

    Reply
    1. Dr. Barry Boyd Post author

      Dear Natalie,

      Thank you for your interest in reposting my post on your blog on your website. I did take a look at your site and are fine with your reprinting it. I would, however, appreciate if you would provide a reciprocal link to this blog and my website, http://www.drbarryboyd.com. I will be writing much more on the subject of environmental factors and breast cancer risk and address what people don’t know about hereditary breast cancer in future posts.

      Dr.Barry Boyd
      Twitter: @drbarryboyd
      LinkedIn: drbarryboyd
      Facebook: drbarryboyd,Cancer:BeyondConventionalTherapy

      Reply
      1. Natalie Palmer

        Hi Dr. Boyd,
        Excellent! Thank you.
        I will also provide a reciprocal link to this blog and your website.
        May I also include your photo with the post?
        All the best,
        Natalie

  2. Maxine Thomas, MD

    Problem is that the “established medical community” cannot have the conversation with the public. Where did the belief that the breast cancer gene was the end all be all in the first place–that community. When I say to people “Most women who get breast cancer DON’T have the BRCA gene”, they are surprised! The broad medical community doesn’t understand that genes are like piano keys, the environment plays the keys and we are the music!! So, they are not informing their patients of this relationship. The environment can slap a muzzle on a gene [ like BRCA], make is shut up and not express itself! Hence, identical twins who posess all of the same genes, don’t get all of the same diseases.

    Reply
    1. Dr. Barry Boyd Post author

      My point exactly. My own research in large population surveys has demonstrated the same understanding. A problem of poor media coverage and inadequate attention by the medical profession in educating the public at large. I hope to help improve that in the future.

      BB

      Reply
  3. Pingback: Breast Cancer: Having The Gene Is Not Destiny

  4. Mary Matthews

    Thank you so much for this information and I am so glad to hear someone in the medical profession questioning the way that the huge amounts of money raised in the name of breast cancer research is being spent. I look forward to the next blog. People seem to have their heads in the sand on this and dont dare to question what is really going on.

    Reply
  5. Dr Marcus Hewitson

    This is a very important message you articulate Barry. Presumably the amount of women with BRCA mutations is quite stable, however the expression of this gene has skyrocketed, from 20% (life time risk) to somewhere near 80-90%, in our lifetimes (figures provided above). This points towards epigenetic/environmental factors as a critical trigger, not just to breast cancer/s but likely a plethora of the diseases of our time, including cancers, the diabesity epidemic, neurodegenerative diseases, neurodevelopmental problems (autism)….I look forward to the next installment.

    Reply
    1. Dr. Barry Boyd Post author

      Appreciate you comment.These are exactly the issue which I will address in my next blog post What indeed are the environmental factors that have contributed to both hereditary and sporadic (non-hereditary) breast cancer.
      BB

      Reply
    1. Dr. Barry Boyd Post author

      Hi Jeanne, Here are my thoughts. Before recommending Se supplementation, I believe it is important to know baseline Se levels. In the Cancer Prevention Study (Se to lower non melanoma skin cancer that showed no effect on skin cancer incidence but did demonstrate a lower risk of colorectal, lung and prostate cancer) when they retrospectively assessed the effect of Se supplementation by baseline level, those in the lowest tertile had a lower cancer risk while those in the upper third of baseline Se had a higher risk. Knowing your baseline level should determine benefit. Love to hear your thoughts about this. Never mind source of selenium, it’s another issue.

      Reply
      1. Jeanne M. Wallace, PhD, CNC

        Absolutely a wise point to screen and supplement only those who are identified deficient. Of course a key question becomes “what should be the cutoff level?” Population-based reference ranges are not very meaningful for individuals seeking to optimize function & wellness. In BrCa1 carriers, selenium supplementation may reduce rates of DNA damage accumulation to normal levels even when baseline selenium level is “normal”. Indeed, BrCa1 carriers may actually have greater need for selenium than average population. It would be awesome to see the Clark et al., data stratified by p53 status and insulin resistance markers too, now that we understand more how these impact cancer epigenetics.

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