Global implementation of hereditary cancer care in gynecologic oncology: Development and evaluation of the Hereditary Cancer Care Implementation Index

This study develops and evaluates a pragmatic framework for benchmarking hereditary cancer care implementation in gynecologic oncology and identify gaps between testing access, policy adoption, and preventive care delivery to evaluate genetic counselor workforce capacity as an independent implementation correlate across different health system settings. We conducted an international implementation assessment across 36 countries representing eight geographic regions and diverse socioeconomic contexts. The Hereditary Cancer Care Implementation Index (HCCII) was developed using predefined implementation domains, including testing access, policy and guideline integration, preventive intervention uptake, and life-course care, while genetic counselor workforce capacity was assessed separately as an implementation determinant. Publicly available data, national guidelines, published reports, and professional society resources were systematically reviewed and scored using standardized criteria. Country-level performance was evaluated descriptively and explored in relation to implementation domains and structural health system characteristics. HCCII scores ranged from 0 to 12 across 36 countries. Ten countries (27.8%) achieved Tier I implementation (score 10-12), while 14 countries (38.9%) scored in the lowest tier (0-3) and 19 lacked nationally documented data on preventive intervention uptake. Testing infrastructure and policy readiness were more developed than preventive care delivery across all regions. A persistent Access-Delivery gap was identified even among high-income countries, indicating that implementation capacity does not reliably translate into delivery of risk-reducing interventions. Hereditary cancer care implementation remains highly variable worldwide. The HCCII provides a pragmatic benchmarking framework for evaluating implementation across health systems. Our findings highlight a persistent gap between genetic testing capacity and translation into preventive care, including in high-income settings, emphasizing the need for implementation strategies that prioritize delivery, equity, and sustainability alongside expansion of testing services.