Tuesday, February 26, 2008

BRCA genes and the women who worry about them

Tumor suppressor genes are worthy bits of genetic info that produce DNA-repair proteins. Left uncorrected, broken DNA can lead to cells no longer subject to orderly growth and development. Unfortunately, tumor suppression genes are also subject to mutated DNA which then produces faulty proteins unable to do their fix-it jobs. Persons who inherit abnormal copies of BRCA1 or BRCA2 are particularly susceptible to ovarian, breast, or prostate cancers.

Women in Denver with a strong family history for either of these cancers can sign up for care through the Rocky Mountain Cancer Center's High Risk Breast Cancer Clinic at Rose Hospital. Drs. Dev Paul and Michele Basche along with genetic specialists evaluate risk and may recommend adding MRI surveillance to annual mammograms as well as genetic testing for BRCA mutations.

According to the Myriad model based on my family history and ethnic background, my risk for a BRCA mutation was 16%. My insurance approved genetic testing (although they will doubtless end up paying far less for it than I will), and I was eager to know the outcome. Fortunately, my test was negative.

One of the things that makes BRCA testing more appealing than other genetic inquiries, say one into Alzheimer's risk, is that something can be done if the test is positive. A newly published study* in the Journal of Clinical Oncology confirms that the current strategy of removing the ovaries of BRCA-mutation positive women is beneficial to their long-term outcomes.

When the researchers compared women with BRCA1 or BRCA2 mutations who either underwent oophorectomies or not, those who chose surgery had a significantly reduced risk of cancer compared with the control group. Specifically, risk reducing oophorectomy was associated with an 85% reduction in BRCA1-associated gynecologic cancer risk and a 72% reduction in BRCA2-associated breast cancer risk.

One of my patients with a BRCA2 mutation (2 sisters, a mother, and a cousin all dead or dying from cancer) was in yesterday, completely satisfied with her decision to undergo this surgery. She had a laparoscopic removal of the ovaries with Dr. Michael Moore in Denver, and declared him "the best."
Kauff, N, et al. J Clin Oncol. 2008 Feb 11 [Epub ahead of print]


rlbates said...

What happens if they haven't had children? Makes the choice even more difficult, doesn't it? Still I think I would go for the oophorectomy with those odds.

JeanMac said...

Food for thought- I don't need them anymore:)

Anonymous said...

My encounter with the BRCA mutations screening was a little different than usual. My mom was diagnosed at 58 -- many years ago -- with cancer widely metastasized throughout her abdomen. My older sister died at 51 from endometrial cancer. After my sister's death, my GYN urged me on the basis of a "hunch" to get the BRCA testing. I put it off for too long, but finally did it. Much to my surprise (but not my doctor's) it came back positive for BRCA1. I am 4 weeks out from a hysterectomy-oophorectomy. Getting rid of my ovaries has been a huge relief. In my down time I have been reading about options for dealing with the increased breast cancer risk. I am lucky that my childbearing years are behind me. I think we are all lucky to be living in an era when this testing is available. Thanks, Dr. Paley, for addressing this important topic

Mauigirl said...

Very helpful - it makes it a hard decision for younger women but certainly if it were me I wouldn't hesitate. In fact, I wonder if I should have the test myself - I'm half Jewish (my father's side) and I know the mutation is more common in certain Jewish bloodlines. However, as far as I know, his female ancestors were not prone to cancer of any kind, although his mother died in her 60's so it's hard to say for her.

Anonymous said...

I have another comment about this that just came up today. When my BRCA 1 result came back positive, my sister informed her doctor. Her doctor recommended she be tested --a rational response, to be sure. And even though she has a 50/50 chance of having the mutation, she is now wishing she hadn't jumped the gun on getting this information plastered all over her medical record because she is anticipating self-employment in the next few years. Insurability will be an issue. In retrospect, she wishes she would have delayed telling her doctor about my result, gotten the test privately through Myriad -- paying for it herself. That way, if it is negative for her, there would be no damaging information in her file about the BRCA mutation. It makes me think that one needs to take a step back and be a little more methodical in dealing with a positive BRCA result in a family member.