Cost-effectiveness of routine screening for Lynch syndrome in colorectal cancer patients up to 70 years of age

Purpose: To assess the cost-effectiveness of routine Lynch syndrome (LS) screening among colorectal cancer (CRC) patients <= 70 years of age. Methods: A population-based series of CRC patients <= 70 years of age was routinely screened for LS. We calculated life years gained (LYG) and incremental cost-effectiveness ratios (ICERs) for different age cutoffs and comparing age-targeted screening with the revised Bethesda guidelines. Results: Screening 1,117 CRC patients identified 23 LS patients, of whom 7 were <= 50 years of age, 7 were 51-60, and 9 were 61-70. Additionally, 70 LS carriers were identified among relatives (14, 42, and 14 per age category). Screening amounted to 205.9 LYG or 43.6, 118.0, and 44.3 LYG per age category. ICERs were (sic)4.226/LYG for screening CRC patients <= 60 years of age compared with those <= 50 years and (sic)7.051/LYG for screening CRC patients <= 70 years compared with those <= 60 years. The revised Bethesda guidelines identified 70 of 93 (75%) LS carriers. The ICER for LS screening in CRC patients <= 70 years of age compared with the revised Bethesda guidelines was (sic)7.341/LYG. All ICERs remained less than (sic)13.000/LYG in one-way sensitivity analyses. Conclusion: Routine LS screening by analysis of microsatellite instability, immunohistochemistry, and MLH1 hypermethylation in CRC patients <= 70 years of age is a cost-effective strategy with important clinical benefits for CRC patients and their relatives.