Women from families in which many individuals have developed breast and/or ovarian cancer may request for DNA-testing. A DNA-test result may disclose their own risks to develop cancer (again),... Show moreWomen from families in which many individuals have developed breast and/or ovarian cancer may request for DNA-testing. A DNA-test result may disclose their own risks to develop cancer (again), their relatives__ risks and subsequent options for medical surveillance. This thesis describes several multicenter studies in the Netherlands about the psychological and medical impact of DNA-testing on the lives of these women and their relatives. Despite their accurate understanding of the global meaning of DNA-test result, many participants interpreted the result differently from what the genetic-counselor had actually communicated. Like in a children__s whisper game, their relatives also misinterpreted the information communicated by the first messenger. The messengers__ misinterpretation was not only related to their inaccurate thoughts about heredity and cancer in general, but also to their feelings, and especially to their unfulfilled need for certainty, sense of self and unresolved existential issues. The presence of misinterpretations predicted the extent of the counselees' distress and the medical decisions after DNA-test result disclosure. The study results are described in their historical and theoretical context, followed by practical clinical suggestions for genetic-counselors and psychologists. For instance, we suggest that genetic-counselor try to avoid the communication of ambiguous DNA-test results that do not have medical consequences. Show less
The cumulative lifetime risk of developing breast cancer for a Dutch woman is about 12%. In some families breast cancer seems to occur even more frequently or women fall ill at a relatively young... Show moreThe cumulative lifetime risk of developing breast cancer for a Dutch woman is about 12%. In some families breast cancer seems to occur even more frequently or women fall ill at a relatively young age. Such families may have a genetic susceptibility towards breast cancer. To learn more about the likelihood of this susceptibility actually being present, members of such families may request genetic counselling and DNA-testing. The main purpose of this thesis is to provide more insight into some effects of genetic counselling and DNA testing for breast cancer. We address effects on: (a) risk perception; (b) psychological distress; and (c) intentions for risk-management behaviour. Regarding the effects of DNA testing, special attention is paid to women who receive a so-called uninformative DNA-test result. The data of this thesis do not provide support for one of the two hypotheses which has been postulated about the impact of an uninformative result. They suggest that, as a group, women seem to be reassured upon learning their uninformative result, but to a lesser extent than women who received a true negative result. Only a small minority of women with an uninformative result incorrectly concluded that the chance of a mutation being present was non-existent. Show less
