HUM-MOLGEN archive: ETHI: BRCA testing

Just one response to the recent posting on BRCA screening. After this post was received by HUM-MOLGEN, there was a press report of a Department of Defense/Mayo Foundation study which found an 85-90% reduction in breast cancer incidence among 1000+ women who had had prophylactic mastectomies between 1960 and 1993. The ETHI topic welcomes submissions of interesting queries, observations or just plain musings on the social ethical and legal aspects of genetics. Hans Goerl ETHI editor ***************************************************************************** ************** From: "Mark Robson <Robson_Mark/mskcc_HG@MSKMAIL.MSKCC.ORG> I would like to briefly respond to Dr. Krul regarding his opinions on the utility of BRCA1/2 testing. I agree that BRCA1/2 testing is not suitable for population screening, both because of expense and because of issues of test specificity. However, in families whose history suggests the presence of a susceptibility allele, testing can be helpful for several reasons. First, there are differing degrees of "increased surveillance," and the finding of a BRCA mutation may guide a woman in determining the intensity of her follow-up. As an alternative to increased surveillance, women can and do elect prophylactic surgery. Whether this approach is "better" than surveillance remains a research question. While I agree that cancers do occur after prophylactic mastectomy (or oophorectomy), evidence is accumulating as to the efficacy of the procedures in substantially reducing risk, even in high-risk cohorts. I am completely unaware of prophylactic surgery having been performed in the s setting of a "false-positive" BRCA mutation analysis. If Dr. Krul has knowledge of such cases, I would encourage him to submit them for peer-review, as this information would be of importance to the clinical cancer genetic community. Until such peer-review has taken place, I would encourage him and others not to propogate unsubstantiated rumors. Next, BRCA mutations confer a risk of second malignancies, particularly ovarian cancer but possibly also colon and prostate. Surveillance for these malignancies is NOT usually performed in a woman with a simple family history of breast cancer. Accordingly, women found to have a mutation may well embark upon a different surveillance program than they would have in the absence of the information. Finally, women (and men) from hereditary breast or breast-ovarian families often suffer considerable anxiety as a consequence of their family histories. In a family with a documented mutation, the finding that an individual does not harbor that mutation signifies that her breast and ovarian cancer risk is most likely that of the general population. This allows her to follow population screening guidelines rather than intensive surveillance guidelines, and often provides significant relief from anxiety. We have much to learn about inherited susceptibility to breast and ovarian cancer in general, and BRCA1/2 in particular. However, the information gained from testing is already proving helpful to selected families when performed with informed consent in the context of appropriate genetic counseling. The major potential barriers to the beneficial application of genetic testing are not those described by Dr. Krul, but social concerns such as insurance and employment discrimination. Mark Robson, MD New York, NY ***************************************************************************** *************** HUM-MOLGEN - Internet Communication Forum in Human Genetics E-mail: HUM-MOLGEN@nic.surfnet.nl To SUBSCRIBE: send "subscribe hum-molgen" to listserve@nic.surfnet.nl To change your TOPICS send "set topics + ____" or "set topics -____" to the same address. WWW: http://www.informatik.uni-rostock.de/HUM-MOLGEN/ http://linkage.rockefeller.edu/hum-molgen/ Phone: 020-566 4598 (The Netherlands), (206) 386-2101 (USA) Fax: 020-691 6521 (The Netherlands), (206) 386-2555 (USA) --------------------------------------------------------------------