Understanding shared and sex-specific considerations in hereditary breast and ovarian cancer (HBOC) testing decision-making in Singapore.

Hereditary breast and ovarian cancer (HBOC) genetic testing identifies pathogenic variant carriers to guide cancer risk management. Although prior research suggests that healthcare decisions-including risk assessment, screening, and treatment-may differ between males and females, the influence of assigned sex at birth on HBOC testing decisions remains underexplored. Twenty-eight participants (10 males, 18 females) considering HBOC testing were recruited from the Cancer Genetics Service at the National Cancer Centre Singapore. Semi-structured interviews, informed by literature review and expert input, were conducted, and a codebook thematic analysis was applied to identify factors influencing testing decisions, with attention to differences between males and females. Five major themes were identified in decision-making: personal health perceptions and psychological readiness; family influences on decision-making; seeking support amid uncertainty; clinical expectations of genetic testing; and system-level barriers to accessing genetic services. Male participants' decisions were shaped primarily by family and clinical support and psychosocial needs, whereas female participants' decisions were influenced by cancer status and social factors, with greater informational needs and misconceptions. HBOC testing decisions reflect sex-specific needs, with males demonstrating greater psychosocial and clinical support requirements and females expressing higher informational needs. These findings underscore the importance of tailoring genetic counseling to sex-specific considerations while ensuring individualized support for all patients.