The cost-effectiveness of genetic testing strategies for Lynch syndrome among newly diagnosed patients with colorectal cancer.

PURPOSE: To estimate the cost-effectiveness of genetic testing strategies to identify Lynch syndrome among newly diagnosed patients with colorectal cancer and to offer targeted testing to relatives of patients with Lynch syndrome.

METHODS: We calculated incremental costs per life-year saved for universal testing relative to no testing and age-targeted testing for strategies that use preliminary genetic tests (immunohistochemistry or microsatellite instability) of tumors followed by sequencing of mismatch repair genes. We also calculated incremental cost-effectiveness ratios for pairs of testing strategies.

RESULTS: Strategies to test for Lynch syndrome in newly diagnosed colorectal tumors using preliminary tests before gene sequencing have incremental cost-effectiveness ratios of or=$700,000 per life-year saved relative to the lowest cost strategies. Increasing the number of relatives tested would improve cost-effectiveness.

CONCLUSION: Laboratory-based strategies using preliminary tests seem cost-effective from the US health care system perspective. Universal testing detects nearly twice as many cases of Lynch syndrome as targeting younger patients and has an incremental cost-effectiveness ratio comparable with other preventive services. This finding provides support for a recent US recommendation to offer testing for Lynch syndrome to all newly diagnosed patients with colorectal cancer.