Purpose: Patients and relatives have varying preferences for genetic testing and interventions related to hereditary cancer syndromes. We examined how the impact of these services on quality of life (QoL) affects the cost-effectiveness of screening for Lynch syndrome among probands newly diagnosed with colorectal cancer and their relatives.
Methods: We constructed a state-transition model comparing screening strategies (clinical criteria, prediction algorithms, tumor testing, and upfront germline testing) with no screening to identify Lynch syndrome. The model incorporated individuals' health state utilities after screening, germline testing, and risk-reducing surgeries, with utilities persisting for 12 months in the base case. Outcomes consisted of quality-adjusted lifeyears (QALYs), costs, and cost per QALY gained. Sensitivity analyses assessed how the duration and magnitude of changes in QoL influenced results.
Results: Multiple screening strategies yielded gains in QALYs at acceptable costs compared with no screening. The preferred strategy-immunohistochemistry of tumors followed by BRAF mutation testing (IHC/BRAF)-cost $59,700 per QALY gained in the base case. The duration and magnitude of decreases in QoL after decisions related to germline testing and surgeries were key determinants of the cost-effectiveness of screening. IHC/BRAF cost >$100,000 per QALY gained when decrements to QoL persisted for 21 months.
Conclusion: Screening for Lynch syndrome in the population is likely to yield long-term gains in life expectancy that outweigh any short-term decreases in QoL, at acceptable costs. Counseling for individuals should aim to mitigate potential negative impact of genetic testing and risk-reducing interventions on QoL.