Perspectives on Preimplantation Genetic Testing for Monogenic Disorders Among Japanese Patients With Hereditary Breast Cancer Undergoing Fertility Preservation: Insights From the First Japanese Survey

Purpose Preimplantation genetic testing for monogenic disorders ( PGT ‐M) offers BRCA variant carriers the option of preventing hereditary cancer transmission. We investigated the awareness and attitudes toward PGT ‐M among patients with breast cancer who underwent fertility preservation. Methods A questionnaire‐based survey was administered to 264 patients with breast cancer who were eligible for oocyte or embryo cryopreservation at in vitro fertilization clinics between October 2024 and March 2025. A total of 161 valid responses were analyzed. The survey assessed BRCA testing status, PGT ‐M awareness, willingness to undergo PGT ‐M, and opinions on future availability. Results The uptake rate of BRCA1 /2 testing was 53.4%; 14% of the respondents were variant carriers. Only 16.8% had prior awareness of PGT ‐M, and 47.8% expressed a willingness to use PGT ‐M if available. Among BRCA ‐variant carriers, 3.3% reported that they would consider PGT ‐M, and 75% believed it should be made available upon request. Overall, 68.3% supported information sharing between oncology and fertility providers. Conclusion These findings highlight the importance of expanding reproductive options and patient awareness of PGT ‐M in the care of patients with hereditary cancer. Discussions should focus on how best to provide accurate information and enable informed reproductive choices for those at genetic risk.