Rabu, 05 Oktober 2016

Should You Get Tested for the Breast Cancer Genes?

October is Breast Cancer Awareness Month, and I couldn't possibly pass up an opportunity to address this important topic.

Superstar Angelina Jolie’s shocking decision to obtain a preventative bilateral mastectomy drew great attention and headlines towards the gene cancer testing that more women are contemplating to prevent breast cancer—the most common cancer in women in the United States. 

When my own sister was diagnosed with breast cancer several years ago, I watched her experience each phase of this taxing illness with a very different patient perspective. And yet, people are still confused surrounding breast cancer gene testing.  My sister’s general surgeon attempted to seek insurance approval for her to get gene testing, given her rather young diagnosis in her 40s, but was denied.  My sister was baffled: why would the insurance companies deny such an importance piece of information that can possibly help her other three sisters given her young age of diagnosis with breast cancer?

It’s not always so simple.  Let me explain what the process of breast cancer gene testing really entails. 

What Is Genetic Testing?

The mostly common involved and most familiar breast cancer genes are the BRCA-1 and BRCA-2 genes. This sort of gene testing can be performed on blood, saliva, or even cheek swabbing.  The challenge? Hundreds of genes involving these two mutations have been discovered. Therefore, obtaining a complete test for all involved possibilities can cost up to 4,000 dollars. If patients meet certain criteria, however, insurance may cover up to 90% of the testing cost. What may be less costly and more simple, however, is if you already have an identified gene in another relative, in which testing can be more targeted and therefore much less costly. 

Besides this BRCA gene testing, further testing involving large genomic rearrangements (or what is referred to as “LR”) may be considered—especially in people of Latin American, Caribbean, and Middle Eastern descent who are at higher risk of testing positive.

Who Is at Increased Risk of Testing Positive for Breast Cancer Genes?

Before we dive deeper into this topic, it’s important to note that not everyone should have gene testing. First, let's learn what populations may truly be at higher risk of developing breast cancer, and may possibly consider gene testing:

  • Those with a first degree relative with breast cancer, most especially with multiple first-degree relatives with breast cancer
  • Those with family history of male breast cancer
  • Those with family history of both breast and ovarian cancer
  • Those with a known family member with a positive breast cancer gene
  • Younger age at the onset of diagnosis, below age 50
  • Recurrent breast cancer in the same patient
  • Bilateral breast cancer
  • Ashkenazi Jewish ethnicity

​Patients who desire genetic testing should strongly consider both pre- and post-genetic counseling because it may be one of the most complex medical decision-making processes of their life.  Getting tested and basing any decisions on this testing would truly require expertise in this not-so-easy-to-understand field.

Most hereditary breast and ovarian cancer genes (which often run in families together) involve one of two specific genes, the BRCA-1 and BRCA-2.  But most patients who undergo testing do not have a mutation in either gene. That’s right—most breast cancer is not hereditary. Hereditary breast cancer is uncommon compared to sporadic diagnoses.

But if given your personal history and your family history, your physician deems you at higher risk, being referred to a board-certified genetic counselor should be the very first step in the testing process. 

A genetic counselor will likely obtain a detailed family and pedigree history, often at least one or two generations back, including both maternal and paternal families.  Then, they will review mathematical models of risk assessments with potential gene involvement based on your family and personal history. 


Risks and Benefits of Genetic Testing

Genetic testing is not exactly cut and dry. The repercussions of determining potential gene involvement in a patient may be greater than you think, and involve complex medical decision making based on statistics and potentially an over-burden on a patient who may never have to combat this illness even if testing positive. 

It’s important to think of the following scenarios before you consider genetic testing:

What happens if you do test positive for a breast cancer gene? It doesn’t mean you will actually develop cancer. Many people can carry genes without ever displaying their effects.  Will it change you and your doctor’s medical decision making in the following instances:  if a high risk gene, medium risk gene, or low risk gene was found?  If it wouldn’t change your management, ask yourself why get tested in the first place, especially if it will cause more harm than good (i.e, more psychosocial distress)?

What happens if the gene testing is negative? Will you rest easy? Or, will you feel “survivor's guilt” within your family that could diminish your mental health? Here are some of the reasons to consider if you have inconclusive or negative testing results:

  • The testing you obtained may not have included the gene involved
  • The testing you obtained may not have been capable of testing the gene involved
  • The gene involved may be sporadic and not inherited
  • There may be an identified gene mutation whose significance is unclear
  • The gene involved may be simply a normal variant

These are all very possible scenarios for which to prepare yourself.

What if your testing is ultimately inconclusive?

What if your testing is ultimately inconclusive? Will you continue further and further testing as the proximate steps in quest for an answer to a question that may never be concrete? Will you have to pay out of pocket for this further costly testing?

The bottom line: If you are considering breast cancer gene testing, ask your doctor for a referral to a genetic counselor for both pre- and post-genetic counseling. The type of testing you pursue, its limitations, cost considerations, interpretation of results, and decision making after obtaining results requires great knowledge and experience to sort through.

My advice: Don't attempt this complex and potentially emotional journey on your own. 

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Please note that all content here is strictly for informational purposes only. This content does not substitute any medical advice, and does not replace any medical judgment or reasoning by your own personal health provider. Please always seek a licensed physician in your area regarding all health related questions and issues.

 



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