Objective: Assess the ability of a Manitoba instituted Lynch Syndrome (LS), an autosomal dominant cancer syndrome, screening protocol to identify carriers in colorectal cancer (CRC) patients as compared to literature.

Methods: Three hundred sixteen CRC resection tumour cases, patient age 70, were screened for a LS profile over 18 months. Immunohistochemistry for mismatch repair deficiency (MMRD), v-raf murine sarcoma viral oncogene homolog B1 sequencing, and microsatellite instability strategies were used to determine a likelihood of LS. Genetic counselling was recommended to suspected carriers.

Results: MMRD was reported in 50(16%) cases; 3(0.9%) deficient (d) MutS homolog 6 (MSH6), 8(2.5%), d MutS protein homolog 2 (MSH2)/dMSH6, 5(1.6%) d Postmeiotic segregation increased 2 (PMS2), and 34(10.7%) d MutL homolog 1 (MLH1)/dPMS2. Seventeen patients underwent germline testing; 9(2.8%) LS mutations were identified.

Conclusion: A confirmed LS mutation in 2.8% of cases is a percentage comparable to literature and supports continued protocol utilization.