Background 
Germline BRCA1/2 (gBRCA1/2) testing is essential for the personalization of breast cancer care, affecting surveillance, prognosis, treatment selection, recurrence prevention strategies, and family risk assessment. Oncogenetics services in Ukraine remain in their initial phase of integration into the national healthcare system. To note, until 2021, next-generation sequencing (NGS) was not even part of the standard oncology practice. Limited oncologist awareness, insufficient interdisciplinary communication, and unclear referral pathways initially constrained the use of genetic testing in cancer care. This study evaluates whether empowering oncologists through multidisciplinary education can improve BRCA1/2 testing practice within the breast cancer care system. 

Methods 
We conducted a national real-world health system study between January 2023 and December 2025. At the beginning of the study, a patient survey on disclosing information concerning genetic testing among breast cancer patients was conducted. The educational intervention for oncologists comprised multidisciplinary activities, including regional round tables, conferences, webinars, and seminars arranged quarterly across all the Ukrainian regions and involving oncologists, pathologists, molecular geneticists, and genetic counselors. All the educational activities focused on the indications for gBRCA1/2 testing, patient selection criteria, and integration of genetic results into treatment planning. To assess baseline patient-facing practice, a cross-sectional study on information disclosure regarding genetic testing and its perceived impact on disease management was conducted.? At the system level, we used aggregated laboratory data to compare the gBRCA1/2 testing activity and the proportion of pathogenic and likely pathogenic gBRCA1/2 variants (PV/LPV) detected before, during, and after the educational intervention. 

Results 
Survey responses demonstrated that patients received limited information regarding genetic testing, its value and its impact on BC management. Only 19,9% of patients reported being informed about genetic testing, indicating significant gaps and missed opportunities for hereditary cancer identification and personalized care. Educational interventions were associated with an increase in genetic testing rates. Following multidisciplinary educational empowerment of oncologists, the uptake of gBRCA1/2 testing increased steadily across all regions of Ukraine. Over the 2023-2025 period, the number of tests elevated progressively, reflecting the increased oncologist awareness of genetic testing and its integration into clinical practice. Educational meetings also facilitated collaboration of oncologists with pathologists, geneticists, and genetic counselors. This led to better patient selection and more streamlined referral pathways.? Consequently, the proportion of identified gBRCA1/2 carriers increased from 9,64% in 2023 to 20,4% in 2025, reflecting a shift toward targeted, efficient and clinically relevant testing rather than indiscriminate expansion. 
 
Conclusions 
Multidisciplinary educational empowerment of oncologists in Ukraine has resulted in more targeted and clinically meaningful gBRCA1/2 testing in patients with BC. By enabling oncologists to effectively use oncogenetics in their decision-making process and collaborate with diagnostic specialists, the testing has become more accessible and diagnostically productive. This study demonstrates that oncologist-focused educational empowerment is a key health system lever for effective implementation of precision oncology, particularly in settings with recently introduced molecular diagnostic capabilities