Traditional Roles in a Non‐Traditional Setting: Genetic Counseling in Precision Oncology

Next generation sequencing technology is increasingly utilized in oncology with the goal of targeting therapeutics to improve response and reduce side effects. Interpretation of tumor mutations requires sequencing of paired germline DNA, raising questions about incidental germline findings. We describe our experiences as part of a research team implementing a protocol for whole genome sequencing (WGS) of tumors and paired germline DNA known as the Michigan Oncology Sequencing project (MI‐ONCOSEQ) that includes options for receiving incidental germline findings. Genetic counselors (GCs) discuss options for return of results with patients during the informed consent process and document family histories. GCs also review germline findings and actively participate in the multi‐disciplinary Precision Medicine Tumor Board (PMTB), providing clinical context for interpretation of germline results and making recommendations about disclosure of germline findings. GCs have encountered ethical and counseling challenges with participants, described here. Although GCs have not been traditionally involved in molecular testing of tumors, our experiences with MI‐ONCOSEQ demonstrate that GCs have important applicable skills to contribute to multi‐disciplinary care teams implementing precision oncology. Broader use of WGS in oncology treatment decision making and American College of Medical Genetics and Genomics (ACMG) recommendations for active interrogation of germline tissue in tumor‐normal dyads suggests that GCs will have future opportunities in this area outside of research settings.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/147078/1/jgc40655.pd

Uptake of genetic testing by the children of Lynch syndrome variant carriers across three generations

Many Lynch syndrome (LS) carriers remain unidentified, thus missing early cancer detection and prevention opportunities. Tested probands should inform their relatives about cancer risk and options for genetic counselling and predictive gene testing, but many fail to undergo testing. To assess predictive testing uptake and demographic factors influencing this decision in LS families, a cross-sectional registry-based cohort study utilizing the Finnish Lynch syndrome registry was undertaken. Tested LS variant probands (1184) had 2068 children divided among three generations: 660 parents and 1324 children (first), 445 and 667 (second), and 79 and 77 (third). Of children aged 418 years, 801 (67.4%), 146 (43.2%), and 5 (23.8%), respectively, were genetically tested. Together, 539 first-generation LS variant carriers had 2068 children and grandchildren (3.84 per carrier). Of the 1548 (2.87 per carrier) eligible children, 952 (61.5%) were tested (1.77 per carrier). In multivariate models, age (OR 1.08 per year; 95% CI 1.06-1.10), family gene (OR 2.83; 1.75-4.57 for MLH1 and 2.59; 1.47-4.56 for MSH2 compared with MSH6), one or more tested siblings (OR 6.60; 4.82-9.03), no siblings (OR 4.63; 2.64-8.10), and parent under endoscopic surveillance (OR 5.22; 2.41-11.31) were independent predictors of having genetic testing. Examples of parental adherence to regular surveillance and genetically tested siblings strongly influenced children at 50% risk of LS to undergo predictive gene testing. High numbers of untested, adult at-risk individuals exist even among well-established cohorts of known LS families with good adherence to endoscopic surveillance.Peer reviewe

Which Lynch syndrome screening programs could be implemented in the "real world"? A systematic review of economic evaluations

Purpose: Lynch syndrome (LS) screening can significantly reduce cancer morbidity and mortality in mutation carriers. Our aim was to identify cost-effective LS screening programs that can be implemented in the "real world."Methods: We performed a systematic review of full economic evaluations of genetic screening for LS in different target populations; health outcomes were estimated in life-years gained or quality-adjusted life-years.Results: Overall, 20 studies were included in the systematic review. Based on the study populations, we identified six categories of LS screening program: colorectal cancer (CRC)-based, endometrial cancer-based, general population-based, LS family registry-based, cascade testing-based, and genetics clinic-based screening programs. We performed an in-depth analysis of CRC-based LS programs, classifying them into three additional subcategories: universal, age-targeted, and selective. In five studies, universal programs based on immunohistochemistry, either alone or in combination with the BRAF test, were cost-effective compared with no screening, while in two studies age-targeted programs with a cutoff of 70 years were cost-effective when compared with age-targeted programs with lower age thresholds. Conclusion: Universal or <70 years-age-targeted CRC-based LS screening programs are cost-effective and should be implemented in the "real world

Endoscopic Mucosal Biopsy Sampling of the Colon and the Terminal Ileum

Microscopic pathological examination of ileocolonic tissue is of the utmost importance to diagnose and follow up diseases of the lower gastrointestinal tract. Ileocolonoscopy allows endoscopic tissue acquisition via different methods. In this chapter, endoscopic mucosal biopsy sampling is described