Current condition of genetic medicine for hereditary breast cancer

BRCA1 or BRCA2 (BRCA1/2) germline mutations, which cause hereditary breast and ovarian cancer syndrome, have been studied to develop targeted therapies for these associated cancer types. The BRCA1/2 test has been implemented in more than one hundred medical facilities in a clinical setting in Japan. The purpose of the current study is to document the prevalence and the awareness of genetic medicine for all hereditary breast cancer (HBC) including the BRCA1/2 test in Japan. The self-administered questionnaire was sent to 120 medical facilities where the BRCA1/2 test was provided, and 83 health care professionals participated (response rate, 69.2%). Of the all respondents, 33.7% (N=42) were clinical geneticists, 31.3% (N=26) other physicians, 15.7% (N=13) genetic counselors and 2.4% (N=2) nurses. In the most recent one-year period, in 83.1% of the 69 facilities the number of patients who underwent genetic testing for HBC was <10 and only 4 facilities provided multigene panel testing for HBC. In order to facilitate the access to genetic medicine, the majority of the genetic counselors (58.3%) recognized the need for education of healthcare professionals. Although the awareness of and interests in HBC have increased gradually, the equitable access to precision medicine is considered to be a challenging issue in Japan.