Identifying persons with Lynch syndrome: why and how?

Successful implementation of Lynch syndrome screening in a safety net institution

Lynch syndrome (LS) is the most common cause of hereditary colorectal cancer (CRC), and national guidelines recommend screening patients with CRC for LS. However, there is a paucity of data related to Lynch syndrome in the underserved population, in which unique issues of access, cultural beliefs regarding cancer, language barriers, immigration status, and financial restraints exist. We performed a descriptive, retrospective review of a selective LS screening protocol at an urban safety net hospital between 2009 and 2014 with the aim of describing the detected prevalence of LS as well as reporting the high quality and suboptimal screening rates. A total of 154 cases of CRC were identified over the 5-year period, of which 57 met selective LS screening criteria. Eleven patients had a positive screen, and three patients were diagnosed with LS, leading to an overall detected LS prevalence of 1.9 %. The rate of high quality screen was greater than 90 %, consistent with prior studies. Thus, we show that screening for LS in a safety net hospital can be successful in achieving high quality screening and provide an example for other public hospitals considering implementation of hereditary cancer screening.

When is Genomic Testing Cost-Effective? Testing for Lynch Syndrome in Patients with Newly-Diagnosed Colorectal Cancer and Their Relatives

Varying estimates of the cost-effectiveness of genomic testing applications can reflect differences in study questions, settings, methods and assumptions. This review compares recently published cost-effectiveness analyses of testing strategies for Lynch Syndrome (LS) in tumors from patients newly diagnosed with colorectal cancer (CRC) for either all adult patients or patients up to age 70 along with cascade testing of relatives of probands. Seven studies published from 2010 through 2015 were identified and summarized. Five studies analyzed the universal offer of testing to adult patients with CRC and two others analyzed testing patients up to age 70; all except one reported incremental cost-effectiveness ratios (ICERs) < $ 100,000 per life-year or quality-adjusted life-year gained. Three studies found lower ICERs for selective testing strategies using family history-based predictive models compared with universal testing. However, those calculations were based on estimates of sensitivity of predictive models derived from research studies, and it is unclear how sensitive such models are in routine clinical practice. Key model parameters that are influential in ICER estimates included 1) the number of first-degree relatives tested per proband identified with LS and 2) the cost of gene sequencing. Others include the frequency of intensive colonoscopic surveillance, the cost of colonoscopy, and the inclusion of extracolonic surveillance and prevention options.