N58: The Cost Of Identifying Lynch Syndrome Carriers In Australia

M. Dillon1, 2, M. A. Jenkins2, D. D. Buchanan2, D. A. Ouakrim2, L. Flander2

1 – Aalto University. 2 – The University of Melbourne.


Aim: We estimated the cost of different screening strategies to identify Lynch syndrome (LS) mutation carriers in Australia.

Method: We used a microsimulation to model costs of DNA mismatch repair gene mutation testing for five target population subgroups: i) incident colorectal cancers (CRCs) diagnosed under age 50; ii) under age 70; iii) at any age; iv) unaffected people aged 20-50 years; and v) unaffected people aged 20-80 years. For the incident CRC subgroups, three strategies were considered: multi-gene panel testing; immunohistochemistry (IHC) followed by a multi-gene panel test; and IHC followed by MLH1 methylation testing and a multi-gene panel test. For the strategies targeting the general population (no CRC), only multi-gene panel testing was considered.

Results: IHC followed by panel testing yielded the lowest cost per mutation carrier identified at AU$2,529, AU$6,331, and AU$11,182 for the approaches targeting incident CRCs under age 50, 70 and any age, respectively. For the general population approaches, testing unaffected people aged 20-50 years was the cheapest option (AU$112,282 per carrier identified). Testing incident CRCs under age 50 identified the highest number of carriers (11,774 per 100,000 probands).

Conclusion: Testing incident CRC cases under age 50 years appears as the most effective and cheapest strategy to identify LS mutation carriers.