Stephanie Melillo

EGAPP supplementary evidence review: DNA testing strategies aimed at reducing morbidity and mortality from Lynch syndrome

1. Clarifying how to define the clinical disorder—Lynch syndrome. In this supplementary review, Lynch syndrome refers to individuals with a predisposition to CRC and certain other malignancies as a result of a germline mismatch repair (MMR) gene mutation—including those with an existing cancer and those who have not yet developed cancer. This definition allows planned analyses of clinical validity and utility to be more straightforward. Several recent editorials and publications recommend that the ambiguous term HNPCC be abandoned and that this clarified definition of Lynch syndrome should be used instead. 2. Removing family history from consideration as a preliminary test. A previous evidence review showed that screening performance of both the Amsterdam and the Bethesda criteria to identify individuals with Lynch syndrome were highly heterogeneous, possibly due to differences among the populations tested. In a general population, Amsterdam criteria are associated with relatively low sensitivity (28‐45%), but high specificity (99%), whereas Bethesda criteria are associated with higher sensitivity (73‐91%), but at the cost of lower specificity (82‐77%). Neither provides the necessary high sensitivity/specificity in a reliable and consistent manner. There are also gaps in knowledge relating to the time required to

Client-directed interventions to increase community demand for breast, cervical, and colorectal cancer screening a systematic review

Most major medical organizations recommend routine screening for breast, cervical, and colorectal cancers. Screening can lead to early detection of these cancers, resulting in reduced mortality. Yet not all people who should be screened are screened, either regularly or, in some cases, ever. This report presents the results of systematic reviews of effectiveness, applicability, economic efficiency, barriers to implementation, and other harms or benefits of interventions designed to increase screening for breast, cervical, and colorectal cancers by increasing community demand for these services. Evidence from these reviews indicates that screening for breast cancer (mammography) and cervical cancer (Pap test) has been effectively increased by use of client reminders, small media, and one-on-one education. Screening for colorectal cancer by fecal occult blood test has been increased effectively by use of client reminders and small media. Additional research is needed to determine whether client incentives, group education, and mass media are effective in increasing use of any of the three screening tests; whether one-on-one education increases screening for colorectal cancer; and whether any demand-enhancing interventions are effective in increasing the use of other colorectal cancer screening procedures (i.e., flexible sigmoidoscopy, colonoscopy, double contrast barium enema). Specific areas for further research are also suggested in this report.

Association between 9p21 genomic markers and heart disease: a meta-analysis.

CONTEXT Associations between chromosome 9p21 single-nucleotide polymorphisms (SNPs) and heart disease have been reported and replicated. If testing improves risk assessments using traditional factors, it may provide opportunities to improve public health. OBJECTIVES To perform a targeted systematic review of published literature for effect size, heterogeneity, publication bias, and strength of evidence and to consider whether testing might provide clinical utility. DATA SOURCES Electronic search via HuGE Navigator through January 2009 and review of reference lists from included articles. STUDY SELECTION English-language articles that tested for 9p21 SNPs with coronary heart/artery disease or myocardial infarction as primary outcomes. Included articles also provided race, numbers of participants, and data to compute an odds ratio (OR). Articles were excluded if reporting only intermediate outcomes (eg, atherosclerosis) or if all participants had existing disease. Twenty-five articles were initially identified and 16 were included. A follow-up search identified 6 additional articles. DATA EXTRACTION Independent extraction was performed by 2 reviewers and consensus was reached. Credibility of evidence was assessed using published Venice criteria. DATA SYNTHESIS Forty-seven distinct data sets from the 22 articles were analyzed, including 35 872 cases and 95 837 controls. The summary OR for heart disease among individuals with 2 vs 1 at-risk alleles was 1.25 (95% confidence interval [CI], 1.21-1.29), with low to moderate heterogeneity. Age at disease diagnosis was a significant covariate, with ORs of 1.35 (95% CI, 1.30-1.40) for age 55 years or younger and 1.21 (95% CI, 1.16-1.25) for age 75 years or younger. For a 65-year-old man, the 10-year heart disease risk for 2 vs 1 at-risk alleles would be 13.2% vs 11%. For a 40-year-old woman, the 10-year heart disease risk for 2 vs 1 at-risk alleles would be 2.4% vs 2.0%. Nearly identical but inverse results were found when comparing 1 vs 0 at-risk alleles. Three studies showed net reclassification indexes ranging from -0.1% to 4.8%. CONCLUSION We found a statistically significant association between 9p21 SNPs and heart disease that varied by age at disease onset, but the magnitude of the association was small.

Intervention to increase recommendation and delivery of screening for breast, cervical, and colorectal cancers by healthcare providers a systematic review of provider reminders.

Most major medical organizations recommend routine screening for breast, cervical, and colorectal cancers. Screening can lead to early detection of these cancers, resulting in reduced mortality. Yet, not all people who should be screened are screened regularly or, in some cases, ever. This report presents results of systematic reviews of effectiveness, applicability, economic efficiency, barriers to implementation, and other harms or benefits of provider reminder/recall interventions to increase screening for breast, cervical, and colorectal cancers. These interventions involve using systems to inform healthcare providers when individual clients are due (reminder) or overdue (recall) for specific cancer screening tests. Evidence in this review of studies published from 1986 through 2004 indicates that reminder/recall systems can effectively increase screening with mammography, Pap, fecal occult blood tests, and flexible sigmoidoscopy. Additional research is needed to determine if provider reminder/recall systems are effective in increasing colorectal cancer screening by colonoscopy. Specific areas for further research are also suggested.

Client-Directed Interventions to Increase Community Demand for Breast, Cervical, and Colorectal Cancer Screening

Most major medical organizations recommend routine screening for breast, cervical, and colorectal cancers. Screening can lead to early detection of these cancers, resulting in reduced mortality. Yet not all people who should be screened are screened, either regularly or, in some cases, ever. This report presents the results of systematic reviews of effectiveness, applicability, economic efficiency, barriers to implementation, and other harms or benefits of interventions designed to increase screening for breast, cervical, and colorectal cancers by increasing community access to these services. Evidence from these reviews indicates that screening for breast cancer (by mammography) has been increased effectively by reducing structural barriers and by reducing out-of pocket client costs, and that screening for colorectal cancer (by fecal occult blood test) has been increased effectively by reducing structural barriers. Additional research is needed to determine whether screening for cervical cancer (by Pap test) can be increased by reducing structural barriers and by reducing out-of-pocket costs, whether screening for colorectal cancer (fecal occult blood test) can be increased by reducing out-of-pocket costs, and whether these interventions are effective in increasing the use of other colorectal cancer screening procedures (i.e., flexible sigmoidoscopy, colonoscopy, double contrast barium enema). Specific areas for further research are also suggested in this report.

Fecal DNA testing for Colorectal Cancer Screening: the ColoSure™ test.

Colorectal cancer is the third most common cancer and the second leading cause of cancer-related deaths in the United States. Screening has been shown to be effective in reducing colorectal cancer incidence and mortality. Colonoscopy, sigmoidoscopy, and fecal occult blood tests are all recommended screening tests that have widespread availability. Nevertheless, many people do not receive the evidence-based recommended screening for colorectal cancer. Additional stool-based methods have been developed that offer more options for colorectal cancer screening, including a variety of fecal DNA tests. The only fecal DNA test that is currently available commercially in the United States is ColoSure(TM), which is marketed as a non-invasive test that detects an epigenetic marker (methylated vimentin) associated with colorectal cancer and pre-cancerous adenomas. We examined the published literature on the analytic validity, clinical validity, and clinical utility of ColoSure and we briefly summarized the current colorectal cancer screening guidelines regarding fecal DNA testing. We also addressed the public health implications of the test and contextual issues surrounding the integration of fecal DNA testing into current colorectal cancer screening strategies. The primary goal was to provide a basic overview of ColoSure and identify gaps in knowledge and evidence that affect the recommendation and adoption of the test in colorectal cancer screening strategies.

Horizon scanning for new genomic tests

Purpose: The development of health-related genomic tests is decentralized and dynamic, involving government, academic, and commercial entities. Consequently, it is not easy to determine which tests are in development, currently available, or discontinued. We developed and assessed the usefulness of a systematic approach to identifying new genomic tests on the Internet.Methods: We devised targeted queries of Web pages, newspaper articles, and blogs (Google Alerts) to identify new genomic tests. We finalized search and review procedures during a pilot phase that ended in March 2010. Queries continue to run daily and are compiled weekly; selected data are indexed in an online database, the Genomic Applications in Practice and Prevention Finder.Results: After the pilot phase, our scan detected approximately two to three new genomic tests per week. Nearly two thirds of all tests (122/188, 65%) were related to cancer; only 6% were related to hereditary disorders. Although 88 (47%) of the tests, including 2 marketed directly to consumers, were commercially available, only 12 (6%) claimed United States Food and Drug Administration licensure.Conclusion: Systematic surveillance of the Internet provides information about genomic tests that can be used in combination with other resources to evaluate genomic tests. The Genomic Applications in Practice and Prevention Finder makes this information accessible to a wide group of stakeholders.

Strengthening the reporting of genetic risk prediction studies (GRIPS): explanation and elaboration

Eur J Clin Invest 2011; 41 (9): 1010–1035

Use of genomic profiling to assess risk for cardiovascular disease and identify individualized prevention strategies—A targeted evidence-based review

Purpose: To address the key question of whether using available “cardiogenomic profiles” leads to improved health outcomes (e.g., reduction in rates of myocardial infarction and stroke) and whether these profiles help in making medical or personal decisions.Methods: A targeted evidence-based review based on published Evaluation of Genomic Applications in Practice and Prevention methodologies.Results: No study addressed the overarching question directly. Evidence for the analytic validity of genomic profiles was inadequate for most genes (scale: convincing, adequate, and inadequate), but based on gray data, the analytic sensitivity and specificity might be adequate. For the 29 candidate genes (58 separate associations reviewed), the credibility of evidence for clinical validity was weak (34 associations) to moderate (23 associations), based on limited evidence, potential biases, and/or variability between included studies. The association of 9p21 variants with heart disease had strong credibility with odds ratios of 0.80 (95% confidence interval: 0.77–0.82) and 1.25 (95% confidence interval: 1.21–1.30), respectively, for individuals with no, or two, at-risk alleles versus those with one at-risk allele. Using a multiplicative model, we combined information from 24 markers predicting heart disease and from 13 markers for stroke. The areas under the curves (64.7% and 55.2%, respectively), and overall screening performance (detection rates of 24% and 14% at a 10% false-positive rate, respectively) do not warrant use as stand-alone tests.Conclusion: Even if genomic markers were independent of traditional risk factors, reports indicate that cardiovascular disease risk reclassification would be small. Improvement in health could occur with earlier initiation or higher adherence to medical or behavioral interventions, but no prospective studies documented such improvements (clinical utility).

Strengthening the reporting of genetic risk prediction studies (GRIPS): Explanation and elaboration

The rapid and continuing progress in gene discovery for complex diseases is fuelling interest in the potential application of genetic risk models for clinical and public health practice. The number of studies assessing the predictive ability is steadily increasing, but they vary widely in completeness of reporting and apparent quality. Transparent reporting of the strengths and weaknesses of these studies is important to facilitate the accumulation of evidence on genetic risk prediction. A multidisciplinary workshop sponsored by the Human Genome Epidemiology Network developed a checklist of 25 items recommended for strengthening the reporting of Genetic RIsk Prediction Studies (GRIPS), building on the principles established by prior reporting guidelines. These recommendations aim to enhance the transparency, quality and completeness of study reporting, and thereby to improve the synthesis and application of information from multiple studies that might differ in design, conduct or analysis.