An update on DNA-based BRCA1/BRCA2 genetic counseling in hereditary breast cancer.

The identification of BRCA1 and BRCA2 mutations has enabled physicians to identify persons at high risk for carcinoma of the breast and ovary in hereditary breast-ovarian cancer (HBOC) families. Many physicians have limited knowledge about the effective translation of these new discoveries into clinical practice settings. This problem is further confounded by the limited number of genetic counselors who have experience with cancer genetics. Genetic counseling about DNA test results was provided to 420 patients from 37 HBC/HBOC families. Descriptive data were collected and recorded about their responses to questions posed immediately before and after test results were disclosed. Findings disclosed a significant tendency of patients to overestimate rather than underestimate their risk (P < .001) prior to receiving results. The chief reason for declining to receive results was fear of insurance discrimination. The primary reason that patients sought test results was for their children. Most women reported that, if testing identified them as mutation carriers, they would consider lifetime surveillance and prophylactic surgery. Responses to DNA test results were varied and often unpredictable. Counseling by an appropriately educated and skilled professional is essential to assist people in making decisions regarding testing and health management.