Use of genetic testing and prophylactic mastectomy and oophorectomy in women with breast or ovarian cancer from families with a BRCA1 or BRCA2 mutation.

PURPOSE: To analyze the use of genetic testing, prophylactic mastectomy, and oophorectomy among women with breast and/or ovarian cancer from families with a BRCA1 or BRCA2 mutation. PATIENTS AND METHODS: We examined prospectively the use of BRCA1/BRCA2 testing in all women with a primary breast or ovarian cancer from a consecutive series of 112 high-risk families in which a BRCA1/BRCA2 mutation eventually was identified. The rate of prophylactic bilateral and contralateral mastectomy and prophylactic oophorectomy was analyzed in the women who carried a BRCA1/BRCA2 mutation and who had no metastatic disease at the time of the genetic test disclosure. We examined predictors for genetic test uptake and prophylactic surgery using univariate and multivariate analysis.
RESULTS: Overall, 192 of 220 women (87%) with primary tumors underwent genetic testing. Eleven of these 192 tested women (6%) appeared not to carry the family-specific BRCA1/BRCA2 mutation. Genetic testing occurred significantly more frequently at ages younger than 50 years (P =.04) and in persons with multiple primary tumors (P =.02). Among eligible women, 35 of 101 (35%) requested bilateral or contralateral mastectomy, and 47 of 95 (49%) requested oophorectomy. Women aged younger than 50 years and women who developed their first tumor after the initial identification of a BRCA1/BRCA2 mutation in the family were significantly (both P =.01) more likely to opt for prophylactic bilateral or contralateral mastectomy.
CONCLUSION: In a clinical setting, we show a high demand for BRCA1/BRCA2 testing and for prophylactic surgery by women with breast and/or ovarian cancer from high-risk families.