Objective: To estimate the cost-effectiveness of screening strategies for Lynch syndrome among newly diagnosed endometrial cancer patients.
Methods: A decision analysis compared four strategies to screen women with newly diagnosed endometrial cancer for Lynch syndrome: 1) Amsterdam criteria strategy, where full gene sequencing was performed for women who meet Amsterdam criteria; 2) Sequence-all strategy, where full gene sequencing was performed for all women with endometrial cancer; 3) Sequence aged younger than 60 years strategy, where full gene sequencing was performed for women aged younger than 60 years with endometrial cancer; and 4) immunohistochemistry/single gene strategy, where immunohistochemistry was performed for the DNA mismatch repair genes for all women after single gene sequencing for specific women lacking protein expression. Prevalence rates, probabilities of immunohistochemistry staining loss, and gene mutation rates were calculated from published data. Costs were estimated from Medicare reimbursement rates. Cost-effectiveness ratios and incremental cost-effectiveness ratios were estimated for each strategy.
Results: For the estimated 40,000 women diagnosed annually with endometrial cancer, the sequence-all strategy detects 920 patients with Lynch syndrome at a cost of $105 million. The Amsterdam criteria give the least-expensive strategy ($7 million), but detect the fewest patients (n=83) with Lynch syndrome. The immunohistochemistry/single gene sequencing strategy detects 858 patients at a cost of $17 million; this strategy has an incremental cost-effectiveness ratio of $13,812. The sequence aged younger than 60 years strategy was less effective and more costly than other strategies.
Conclusion: Of the strategies studied, immunohistochemical evaluation of tumor specimens for mismatch repair protein expression after single gene sequencing for patients with endometrial cancer is a cost-effective strategy for detecting Lynch syndrome.
Level of evidence: : III.