Genetic testing for breast-ovarian cancer susceptibility: a regional trial.

To evaluate receptivity to testing for a genetic susceptibility to breast-ovarian cancer, information is needed on the response when the offer is open to all qualifying women in a given region. To qualify in this trial, a woman who had not had breast or ovarian cancer had to have at least two first-degree relatives or one first- and one second-degree relative with breast and/or ovarian cancer, whereas a woman who had had breast or ovarian cancer had to have at least one first-degree relative with breast or ovarian cancer and a first- or second-degree relative without cancer willing to be tested. Of 140 women qualifying and interested enough to return questionnaires requesting baseline information, 111 were referred by their physician and 29 were identified from a regional tumor registry. Of these 140, 112 came for pretest education and 98 of these chose to be tested. Thus, the acceptance rate was 70% for all those returning baseline questionnaires, but 88% for those interested enough to come for pretest education. The most common reasons for accepting testing were to take extra precautions if a mutation were found (42.9%) and to determine if offspring were at risk (24.5%). The most common reasons for declining were anxiety and absence of specific interventions. Factors predicting who chose testing were years of education (p < 0.005) and family closeness (p < 0.02). Fourteen deleterious BRCA1 or BRCA2 mutations were found in 13 of the 87 families actually tested. If the criteria for testing had been three or more affected family members rather than two or more, the number of families tested would have been reduced by 46%, but the number of families found to have a deleterious mutation would have been reduced by only 9%.