Princeton Longevity News

Celebrity health problems often make headlines.  When those problems involve the breasts of Angelina Jolie, a woman “celebrated for her curves” as Maureen Dowd wrote in the New York Times, it is sure to get even more attention.  Hearing that Angelina had a test done that showed she had an 87% likelihood of developing breast cancer creates the impression that there is a test available that can accurately tell every woman her breast cancer risk.  If that is the case, shouldn’t every woman have this test done? 

Angelina’s mother died at 56 from ovarian cancer.  Because there is a genetic link between some cases of ovarian cancer and genetic mutations in two genes, BRCA1 and BRCA2, Angelina opted to have the test done to determine if she inherited such a mutation from her mother.  The test showed that she carried a mutation in BRCA1 that put her at high risk for both breast and ovarian cancer.  She elected to have a double mastectomy to lower her risk of breast cancer and has told interviewers that she plans to soon have her ovaries removed to lower her ovarian cancer risk.

Testing for BRCA1 and BRCA2 is expensive.  The test can be as much as $3,000 and may or may not be covered by your insurance.  There is also the cost of whatever treatment may be undertaken if you turn out to be carrying a high risk mutation.  While public policy experts worry about the cost of that testing and treatment relative to the number of cancers that would actually be prevented, I think it is a safe bet that most women would gladly part with $3,000 if it meant avoiding a high likelihood of dying young.  A policymaker’s threshold for what is a reasonable cost to prevent some else’s cancer death may not be quite the same as what you think is a reasonable cost to save your own life.  “Cost-effective” probably varies depending on whether you are talking about my life or yours.   So let’s put aside the cost considerations for the moment and focus on whether testing for BRCA mutations is actually likely to be helpful.

BRCA1 and BRCA2 are part of a class of genes known as tumor suppressors.  Normally they help to prevent uncontrolled growth of cells.  If a woman has inherited a mutation in those genes, it may alter the effectiveness of this control mechanism. The result can be an increased risk of cancers of the breast, ovaries, uterus, pancreas, colon, stomach, gallbladder and skin.   Men with the mutation may be at increased risk for cancers of the breast, testicle, pancreas or prostate.

The likelihood of carrying one of these genetic mutations is highest in people where there is a strong family history of these cancers.  Ashkenazi Jews (of central and eastern European origin) are also at higher risk for carrying the mutation.  However, not every woman with a family cancer history carries the gene and not everyone who carries the mutations develops cancer.

Having a BRCA mutation increases a woman’s risk of breast about 5-fold (from a 12% risk to about a 60% risk).  But the BRCA 1 and BRCA2 are not the only genetic mutations associated with breast cancers.  Even more importantly, the vast majority of breast cancers are not at all related to BRCA1 or BRCA2 mutations.   Overall, only about one in every 400 to 800 women in the general population carry BRCA mutations.  (The prevalence in Ashkenazi Jews is about 1 in 40).   So, these mutations account for only about 5% of breast cancers.  The other 95% have nothing to do with BRCA mutations and testing for those mutations does not help to identify the risk in those women. Getting tested is not very likely to be helpful in women who are not at high risk of carrying one of these mutations in the first place.  The National Cancer Institute recommends the following guidelines to help in deciding whether you should consider being tested according to your likelihood of having  a harmful mutation in BRCA1 or BRCA2 based on  certain familial patterns of cancer. These patterns include the following:

• For women who are not of Ashkenazi Jewish descent:
  • two first-degree relatives (mother, daughter, or sister) diagnosed with breast cancer, one of whom was diagnosed at age 50 or younger;
  • three or more first-degree or second-degree (grandmother or aunt) relatives diagnosed with breast cancer regardless of their age at diagnosis;
  • a combination of first- and second-degree relatives diagnosed with breast cancer and ovarian cancer (one cancer type per person);
  •  a first degree relative with cancer diagnosed in both breasts (bilateral breast cancer);
  • a combination of two or more first- or second-degree relatives diagnosed with ovarian cancer regardless of age at diagnosis;
  • a first- or second-degree relative diagnosed with both breast and ovarian cancer regardless of age at diagnosis; and
  • breast cancer diagnosed in a male relative.

• For women of Ashkenazi Jewish descent:
  • any first-degree relative diagnosed with breast or ovarian cancer; and
  • two second-degree relatives on the same side of the family diagnosed with breast or ovarian cancer.

If you do elect to get tested, it should be done with the guidance of an oncologist and genetic counselor who can help to put your results in the proper perspective and discuss the treatment options.  While surgery is an option for those at very high risk, other screening and treatment options can also be considered.

For those who do not fall into the risk groups above, we would not recommend screening for BRCA mutations.