Healthcare provider-mediated cascade testing of Lynch syndrome to at-risk family members: an interview study

Cascade testing is often recommended for cancer predisposition syndromes, like Lynch syndrome (LS), to identify at-risk family members. The uptake of cascade testing is typically meditated by the proband's willingness to disclose their results with family members. Of which, cascade testing uptake rates in Singapore has been low, compared to global rates. Studies suggest that healthcare providers (HCPs)-meditated contact of at-risk family improves uptake, yet few have explored how receptive probands and family members are to such a model. Moreover, no studies to date have examined such a model of cascade testing in Asia. To address this gap, we interviewed 17 participants (probands and relatives) in Singapore to evaluate the acceptability and feasibility of HCP-mediated cascade testing for families with LS. Our findings show broad acceptability for HCP-mediated disclosure to relatives, driven by a sense of beneficence. However, HCP involvement introduced three unique issues to disclosure process: (i) their clinical position, which conveys expertise and authority; (ii) relational complexities within family dynamics; and (iii) the notion of family-centric privacy. We propose that HCP-mediated disclosure may be best implemented through a cooperative and flexible process, tailored to each family's unique circumstances. This approach balances the efficiency of providing accurate genetic information whilst sensitively navigating familial relationships, thereby improving uptake while respecting cultural and relational nuances.