Screening and preventive behaviors one year after predictive genetic testing for hereditary nonpolyposis colorectal carcinoma

Lifetime prevalence and correlates of colorectal cancer screening among low-income U.S. Veterans

PURPOSE

The Veterans Health Administration (VHA) is the largest integrated healthcare system in the U.S. While preventive healthcare services are high priority in the VHA, low-income U.S. Veterans experience adverse life circumstances that may negatively impact their access to these services. This study examined lifetime prevalence as well as demographic, socioeconomic, military-specific, and clinical correlates of colorectal cancer (CRC) screening among low-income U.S. Veterans ≥ 50 years of age.

METHODS

Cross-sectional data on 862 participants were analyzed from the 2021-2022 National Veteran Homeless and Other Poverty Experiences study.

RESULTS

Overall, 55.3% (95% confidence interval [CI] 51.3-59.3%) reported ever-receiving CRC-screening services. In a multivariable logistic regression model, never-receivers of CRC screening were twice as likely to reside outside of the Northeast, and more likely to be married (odds ratio [OR] = 1.86, 95% CI 1.02, 3.37), have BMI < 25 kg/m2 [vs. 25- < 30 kg/m2] (OR = 1.75, 95% CI 1.19, 2.58), or ≥ 1 chronic condition (OR = 1.46, 95% CI 1.06, 2.02). Never-receivers of CRC screening were less likely to be female (OR = 0.53, 95% CI 0.29, 0.96), aged 65-79y [vs. ≥ 80y] (OR = 0.61, 95% CI 0.40, 0.92), live in 5 + member households (OR = 0.33, 95% CI 0.13, 0.86), disabled (OR = 0.45, 0.22, 0.92), with purchased health insurance (OR = 0.56, 95% CI 0.33, 0.98), or report alcohol-use disorder (OR = 0.10, 95% CI 0.02, 0.49) and/or HIV/AIDS (OR = 0.28, 95% CI 0.12, 0.68).

CONCLUSION

Nearly 55% of low-income U.S. Veterans reported ever screening for CRC. Variations in CRC-screening behaviors according to veteran characteristics highlight potential disparities as well as opportunities for targeted behavioral interventions.

Mapping psychosocial interventions in familial colorectal cancer: a rapid systematic review

Background

Approximately 5% of colorectal cancer (CRC) cases are part of a well-defined inherited genetic syndrome and up to approximately 30% of these cases have a clinically defined familial basis. Psychosocial interventions in familial colorectal cancer address aspects mainly focused on affective, cognitive and behavioural outcomes. The present review aims to systematically map out the available psychosocial interventions for individuals with a family history of CRC and describe the current state of the research.

Methods

An extensive electronic search was conducted to investigate the literature published until June 2020. Inclusion criteria consisted of quantitative studies published in English that explored the impact of psychosocial interventions for familial CRC, clearly defined the psychosocial intervention offered and included participants with a family history of CRC.

Results

The analysis included 52 articles. Genetic counselling, educational interventions, psychological interventions and multimodal interventions were identified across the studies. In terms of diagnoses, Lynch Syndrome, Familial Adenomatous Polyposis, Familial Colorectal Cancer were the main conditions included in the studies. Affective, cognitive, behavioural aspects and quality of life emerged as the most frequently explored outcomes. The studies included individuals with both personal and familial history of CRC or family history alone.

Conclusions

Our rapid review provides an overview of the literature exploring the impact of psychosocial interventions for familial CRC. The psychosocial interventions identified had an overwhelmingly positive impact across all types of outcomes measured. Genetic counselling appeared to be most beneficial, and this is expected as it is purposively designed to address genetic conditions. Further quantitative analysis of primary empirical research is needed to determine the efficacy and effectiveness of psychosocial interventions as well as the mechanisms through which they exert their effect.

Early detection of duodenal cancer by upper gastrointestinal-endoscopy in Lynch syndrome

Small bowel cancer (SBC) is the malignancy with the highest standardized incidence ratio in Lynch syndrome (LS) patients. Of all SBCs, about 50% are duodenal cancers (DCs), therefore being accessible by esophago-gastro-duodenoscopy (EGD) for surveillance. We asked whether early detection of DC is possible for LS patients undergoing surveillance by EGD and if surveillance should be limited to specific subgroups. Data for LS patients with DC were retrieved from the registry of the German Consortium for Familial Intestinal Cancer. Patients undergoing active surveillance by EGDs (surveillance group) were compared to those who did not (nonsurveillance group) regarding tumor stage at diagnosis. Union for International Cancer Control stages I-IIA were defined as early stage disease and IIB-IV as advanced stage disease. Statistical analysis was performed using Fisher's exact test. Among 2015 patients with pathogenic variants in any mismatch-repair-gene, 47 patients with 49 DCs were identified. In 10% of cases, patients were under 35 years at diagnosis; family and personal tumor history did not correlate with DC diagnosis. Pathogenic germline variants in MSH6, PMS2 or EPCAM were present in 10% of patients. Statistical analysis could be performed on 13 DC patients in the surveillance group and 14 in the nonsurveillance group. Early detection was possible for 71% of patients in the surveillance group and 29% of patients in the nonsurveillance group (P = .021). Early detection of DC by EGD in LS patients is feasible regardless of family history, mutational status and should start no later than 25 years of age.

Evaluation of implementation of risk management guidelines for carriers of pathogenic variants in mismatch repair genes: a nationwide audit of familial cancer clinics

INTRODUCTION

This nationwide study assessed the impact of Lynch syndrome-related risk management guidelines on clinicians' recommendations of risk management strategies to carriers of pathogenic variants in mismatch repair genes and the extent to which carriers took up strategies in concordance with guidelines.

MATERIALS AND METHODS

Clinic files of 464 carriers (with and without colorectal cancer) were audited for carriers who received their genetic testing results in July 2008-July 2009 (i.e. before guideline release), July 2010-July 2011 and July 2012-July 2013 (both after guideline release) at 12 familial cancer clinics (FCCs) to ascertain the extent to which carriers were informed about risk management in accordance with guidelines. All carriers captured by the audit were invited to participate in interviews; 215 were interviewed to assess adherence to recommended risk management guidelines.

RESULTS

The rates of documentation in clinic files increased significantly from pre- to post-guideline for only two out of eight risk management strategies. The strategies with the highest compliance of carriers post-guidelines were: uptake of one or two-yearly colonoscopy (87%), followed by hysterectomy to prevent endometrial cancer (68%), aspirin as risk-reducing medication (67%) and risk-reducing salpingo-oophorectomy (63%). Interrater reliability check for all guidelines showed excellent agreement (k statistics = 0.89).

CONCLUSION

These results indicate that there is scope to further increase provision of advice at FCCs to ensure that all carriers receive recommendations about evidence-based risk management. A multi-pronged behaviour change and implementation science approach tailored to specific barriers is likely to be needed to achieve optimal clinician behaviours and outcomes for carriers.

Uptake and predictors of colonoscopy use in family members not participating in cascade genetic testing for Lynch syndrome

Cascade genetic testing provides a method to appropriately focus colonoscopy use in families with Lynch syndrome (LS). However, research suggests that up to two-thirds at risk to inherit LS don’t participate. Within the United States, no studies have assessed colonoscopy use within this elusive and high-risk subset. We set forth to (1) document colonoscopy use within those not undergoing genetic testing (NGT) and (2) identify factors associated with completing colonoscopy. Data came from a cross sectional survey of families with molecularly confirmed LS. One hundred seventy-six (176) adults participated; 47 of unknown variant status and 129 with variant status known (59 carriers/70 non-carriers). Despite a high level of awareness of LS (85%) and identical recommendations for colonoscopy, NGT reported significantly lower use of colonoscopy than carriers (47% vs. 73%; p = 0.003). Our results show that perceived risk to develop colon cancer (AOR = 1.99, p < 0.05) and physician recommendations (AOR = 7.64, p < 0.01) are significant predictors of colonoscopy use across all family members controlling for carrier status. Given these findings, health care providers, should assess patients’ perceived risk to develop cancer, assist them in adjusting risk perceptions and discuss recommendations for colonoscopy with all members in families with LS.

Trial Registration Clinical Trials.gov Identifier: NCT00004210.

Assessing the adherence to guidelines in Lynch syndrome patients: a pilot study

BACKGROUND

Cancer surveillance is important in the management of Lynch syndrome. In New South Wales, management guidelines for Lynch syndrome are published on the eviQ website. Benefits of cancer surveillance are maximized through adherence to guidelines. This has yet to be investigated in Sydney. Hence, this study aimed to determine the adherence rate of patients to these guidelines, assess their knowledge of the guidelines and determine potential factors hindering regular colonoscopies in these patients.

METHODS

A cross-sectional study was conducted among Lynch syndrome patients from the St Vincent's Hospital Cancer Genetics Unit, Sydney. Patients who appropriately fulfilled our inclusion criteria were mailed a questionnaire. The questionnaire was mailed twice to increase the response rate. Demographic and medical information were collected from patient medical records. Patient responses were analysed to determine adherence to the guidelines.

RESULTS

Sixty-two individuals were invited to participate in this study. Among them, 47 responded (76%) with two being excluded, due to potential confounding factors. Thirty (67%) had their colonoscopies at recommended intervals, while 15 (33%) had delays. Within these two groups, many were ultimately deemed non-adherent to the guidelines due to over-screening with other tests. In total, 31 (69%) participants were considered over-screening for cancer, leaving only seven (16%) participants fully adherent to the guidelines. Only three (7%) had knowledge of the eviQ guidelines.

CONCLUSIONS

Adherence to the eviQ guidelines was poor. The majority of participants were being over-screened for cancer. Knowledge of the guidelines needs to be improved.

The PiGeOn project: protocol of a longitudinal study examining psychosocial and ethical issues and outcomes in germline genomic sequencing for cancer

Background

Advances in genomics offer promise for earlier detection or prevention of cancer, by personalisation of medical care tailored to an individual’s genomic risk status. However genome sequencing can generate an unprecedented volume of results for the patient to process with potential implications for their families and reproductive choices. This paper describes a protocol for a study (PiGeOn) that aims to explore how patients and their blood relatives experience germline genomic sequencing, to help guide the appropriate future implementation of genome sequencing into routine clinical practice.

Methods

We have designed a mixed-methods, prospective, cohort sub-study of a germline genomic sequencing study that targets adults with cancer suggestive of a genetic aetiology. One thousand probands and 2000 of their blood relatives will undergo germline genomic sequencing as part of the parent study in Sydney, Australia between 2016 and 2020. Test results are expected within12–15 months of recruitment. For the PiGeOn sub-study, participants will be invited to complete surveys at baseline, three months and twelve months after baseline using self-administered questionnaires, to assess the experience of long waits for results (despite being informed that results may not be returned) and expectations of receiving them. Subsets of both probands and blood relatives will be purposively sampled and invited to participate in three semi-structured qualitative interviews (at baseline and each follow-up) to triangulate the data. Ethical themes identified in the data will be used to inform critical revisions of normative ethical concepts or frameworks.

Discussion

This will be one of the first studies internationally to follow the psychosocial impact on probands and their blood relatives who undergo germline genome sequencing, over time. Study results will inform ongoing ethical debates on issues such as informed consent for genomic sequencing, and informing participants and their relatives of specific results. The study will also provide important outcome data concerning the psychological impact of prolonged waiting for germline genomic sequencing. These data are needed to ensure that when germline genomic sequencing is introduced into standard clinical settings, ethical concepts are embedded, and patients and their relatives are adequately prepared and supported during and after the testing process.

Colorectal Cancer in the Young

PURPOSE OF REVIEW

Colorectal cancer incidence has been rapidly rising in those under the age of 50 over the last 20 years. This paper will review the epidemiology, clinicopathologic, molecular features, proposed risk factors, and prevention/treatment approach for early onset CRC (EOCRC) patients.

RECENT FINDINGS

EOCRC appears to have a different spectrum of clinical, pathologic, and molecular presentation compared to CRC diagnosed in older individuals. EOCRCs are disproportionately located in the distal colon; these patients tend to present with symptoms, and there is a longer interval between symptoms and diagnosis. There may be a distinct molecular signature, including progression through the microsatellite and chromosomal stable (MACS) pathway and LINE-1 hypomethylation for a subset of EOCRCs. The majority of EOCRCs are sporadic without clear risk factors that would have made the patient eligible for earlier screening. There is an acute need for educational efforts aimed at both providers and patients to raise awareness about CRC in the young. Improving adherence to screening in young patients eligible for screening and emphasizing early evaluation of symptoms are important steps to decreasing the burden of CRC in younger patients. Modeling and empiric data are needed to determine whether our current screening approach should be modified and whether causation and treatment options may be different in a molecular subset EOCRCs.

Choosing not to undergo predictive genetic testing for hereditary colorectal cancer syndromes: expanding our understanding of decliners and declining

While medical research continues to investigate the genetic basis of cancer, and personalised prevention gains momentum, little research has been conducted with the individuals who decline predictive genetic testing for cancer. We recruited individuals who had been offered genetic testing for Lynch syndrome or bi-allelic MUTYH mutations due to their participation in a large, population-based, Australia-wide colorectal cancer study. Thirty-three individuals in mutation-carrying families, unaffected by cancer, who had actively or passively declined testing at one of four decision-making points, took part in a qualitative interview about their decision. Data analysis revealed a typology of 'decliners': (1) uninformed about genetic testing; (2) a weak intention to undergo genetic testing; (3) conditionally declining; and (4) unconditionally declining testing. In this population we found substantial barriers to achieving the benefits promised by predictive genetic testing; a lack of knowledge of the availability of genetic testing; a lack of trust in genetic test information; a desire to see a stronger benefit from genetic testing before proceeding; and a sense that there may be more negative than positive outcomes from genetic testing. These discourses must be addressed if medical research on the genetic basis of cancer continues to be funded, and personalised prevention of cancer continues to be recommended by experts.

How does genetic risk information for Lynch syndrome translate to risk management behaviours?

Background

There is limited research on why some individuals who have undergone predictive genetic testing for Lynch syndrome do not adhere to screening recommendations. This study aimed to explore qualitatively how Lynch syndrome non-carriers and carriers translate genetic risk information and advice to decisions about risk managment behaviours in the Australian healthcare system.

Methods

Participants of the Australasian Colorectal Cancer Family Registry who had undergone predictive genetic testing for Lynch syndrome were interviewed on their risk management behaviours. Transcripts were analysed thematically using a comparative coding analysis.

Results

Thirty-three people were interviewed. Of the non-carriers (n = 16), 2 reported having apparently unnecessary colonoscopies, and 6 were unsure about what population-based colorectal cancer screening entails. Of the carriers (n = 17), 2 reported they had not had regular colonoscopies, and spoke about their discomfort with the screening process and a lack of faith in the procedure’s ability to reduce their risk of developing colorectal cancer. Of the female carriers (n = 9), 2 could not recall being informed about the associated risk of gynaecological cancers.

Conclusion

Non-carriers and female carriers of Lynch syndrome could benefit from further clarity and advice about appropriate risk management options. For those carriers who did not adhere to colonoscopy screening, a lack of faith in both genetic test results and screening were evident. It is essential that consistent advice is offered to both carriers and non-carriers of Lynch syndrome.

An investigation of the factors effecting high-risk individuals' decision-making about prophylactic total gastrectomy and surveillance for hereditary diffuse gastric cancer (HDGC)

Hereditary diffuse gastric cancer has an early onset and poor prognosis, therefore, individuals who carry a pathogenic (CDH1) mutation in the E-cadherin gene (CDH1) are offered endoscopic surveillance and advised to undergo prophylactic total gastrectomy (PTG) in their early to mid-twenties. Patients not ready or fit to undergo gastrectomy, or in whom the genetic testing result is unknown or ambiguous, are offered surveillance. Little is known about the factors that influence decisions to undergo or decline PTG, making it difficult to provide optimal support for those facing these decisions. Qualitative interviews were carried out with 35 high-risk individuals from the Familial Gastric Cancer Study in the UK. Twenty-seven had previously undergone PTG and eight had been identified as carrying a pathogenic CDH1 mutation but had declined surgery at the time of interview. The interviews explored the experience of decision-making and factors influencing risk-management decisions. The data suggest that decisions to proceed with PTG are influenced by a number of potentially competing factors: objective risk confirmation by genetic testing and/or receiving a positive biopsy; perceived familial cancer burden and associated risk perceptions; perceptions of post-surgical life; an increasing inability to tolerate endoscopic procedures; a concern that surveillance could miss a cancer developing and individual's life stage. These findings have implications for advising this patient group.

Universal Versus Targeted Screening for Lynch Syndrome: Comparing Ascertainment and Costs Based on Clinical Experience

BACKGROUND

Strategies to screen colorectal cancers (CRCs) for Lynch syndrome are evolving rapidly; the optimal strategy remains uncertain.

AIM

We compared targeted versus universal screening of CRCs for Lynch syndrome.

METHODS

In 2010-2011, we employed targeted screening (age < 60 and/or Bethesda criteria). From 2012 to 2014, we screened all CRCs. Immunohistochemistry for the four mismatch repair proteins was done in all cases, followed by other diagnostic studies as indicated. We modeled the diagnostic costs of detecting Lynch syndrome and estimated the 5-year costs of preventing CRC by colonoscopy screening, using a system dynamics model.

RESULTS

Using targeted screening, 51/175 (29 %) cancers fit criteria and were tested by immunohistochemistry; 15/51 (29 %, or 8.6 % of all CRCs) showed suspicious loss of ≥1 mismatch repair protein. Germline mismatch repair gene mutations were found in 4/4 cases sequenced (11 suspected cases did not have germline testing). Using universal screening, 17/292 (5.8 %) screened cancers had abnormal immunohistochemistry suspicious for Lynch syndrome. Germline mismatch repair mutations were found in only 3/10 cases sequenced (7 suspected cases did not have germline testing). The mean cost to identify Lynch syndrome probands was ~$23,333/case for targeted screening and ~$175,916/case for universal screening at our institution. Estimated costs to identify and screen probands and relatives were: targeted, $9798/case and universal, $38,452/case.

CONCLUSIONS

In real-world Lynch syndrome management, incomplete clinical follow-up was the major barrier to do genetic testing. Targeted screening costs 2- to 7.5-fold less than universal and rarely misses Lynch syndrome cases. Future changes in testing costs will likely change the optimal algorithm.

Knowledge and Uptake of Genetic Counseling and Colonoscopic Screening Among Individuals at Increased Risk for Lynch Syndrome and their Endoscopists from the Family Health Promotion Project

OBJECTIVES

Individuals whose families meet the Amsterdam II clinical criteria for hereditary non-polyposis colorectal cancer are recommended to be referred for genetic counseling and to have colonoscopic screening every 1-2 years. To assess the uptake and knowledge of guideline-based genetic counseling and colonoscopic screening in unaffected members of families who meet Amsterdam II criteria and their treating endoscopists.

METHODS

Participants in the Family Health Promotion Project who met the Amsterdam II criteria were surveyed regarding their knowledge of risk-appropriate guidelines for genetic counseling and colonoscopy screening. Endoscopy/pathology reports were obtained from patients screened during the study to determine the follow-up recommendations made by their endoscopists. Survey responses were compared using Fisher's Exact and the χ(2) test. Concordance in participant/provider-reported surveillance interval was assessed using the kappa statistic.

RESULTS

Of the 165 participants, the majority (98%) agreed that genetics and family history are important predictors of CRC, and 63% had heard of genetic testing for CRC, although only 31% reported being advised to undergo genetic counseling by their doctor, and only 7% had undergone genetic testing. Only 26% of participants reported that they thought they should have colonoscopy every 1-2 years and 30% of endoscopists for these participants recommended 1-2-year follow-up colonoscopy. There was a 65% concordance (weighted kappa 0.42, 95% CI 0.24-0.61) between endoscopist recommendations and participant reports regarding screening intervals.

CONCLUSIONS

A minority of individuals meeting Amsterdam II criteria in this series have had genetic testing and reported accurate knowledge of risk-appropriate screening, and only a small percentage of their endoscopists provided them with the appropriate screening recommendations. There was moderate concordance between endoscopist recommendations and participant knowledge suggesting that future educational interventions need to target both health-care providers and their patients.

Practical opportunities to improve early detection and prevention of colorectal cancer (CRC) in members of high-risk families

Colorectal cancer (CRC) incidence and mortality are steadily declining and CRC screening rates are increasing in the United States. Although this a very good news, several definable groups still have very low screening rates including younger (under age 50) members of high-risk CRC families. This opinion piece describes five strategies that could be incorporated into routine practice to improve identification and guideline-based screening in members of high-risk families. Routine incorporation of a simple family history screening tool and outreach to high-risk family members could substantially improve guideline-based screening in this population. Identification of CRCs and advanced adenomas in the endoscopy suite defines another group of high-risk families for similar outreach. Lynch syndrome families can be identified by testing CRCs and selected adenomas for microsatellite instability or loss of DNA repair protein expression. Finally, selective addition of aspirin to surveillance endoscopy can decrease the risk of new adenomas and CRCs. The rationale for these strategies as well as mechanisms for their implementation and evaluation in clinical practice is described.

Public attitudes toward genetic risk testing and its role in healthcare

Developments in genomics continue to increase the number of disorders for which genetic testing is available, whether in the primary healthcare system, through direct-to-consumer testing, or as part of expanded newborn screening panels. This paper reviews a robust literature on public attitudes toward genetics and genetic testing. In general, attitudes are positive about genetic research and new genomic technologies, with majorities indicating an interest in genetic testing. However, complex beliefs comprise the public's thinking about genetics. Attitudes are driven by beliefs about the type of genetic research, the personal and clinical utility of tests, and the area of genetics in which testing is applied. Limitations of current research are noted and suggestions made for future research.

Psychosocial consequences of predictive genetic testing for Lynch syndrome and associations to surveillance behaviour in a 7-year follow-up study

We evaluated long-term psychosocial consequences of predictive genetic testing, and surveillance behaviour in Lynch syndrome (LS). We conducted a longitudinal study of 208 participants (62 LS mutation carriers and 146 non-carriers) who provided information on general anxiety (State-Trait Anxiety Inventory), fear of cancer and dying, satisfaction with life, risk and test perceptions, and surveillance behaviour in the baseline questionnaire before testing, and 1 month, 1 year and 7 years post-test. At 7 years, most of the psychosocial variables remained unchanged, regardless of mutation status. Carriers tended to underestimate their colorectal cancer risk but were more worried about their cancer risk than their counterparts. Non-carriers reported a higher degree of satisfaction with their testing decisions (P < 0.05), but had more doubts concerning test result validity than carriers (P < 0.05). All carriers attended a post-test colonoscopy surveillance, while 16% of non-carriers reported colonoscopy examinations. Those non-carriers with doubts about test validity were more likely (P = 0.019) to report post-test colonoscopy. Of the carriers, 17% had an interval longer than 3 years between their colonoscopies. Fear of dying soon, measured at 1-month post-test follow-up was the only psychosocial variable predicting non-compliance in recommended surveillance. No adverse psychosocial consequences were detected, and respondents were satisfied with their decision to testing 7 years post-test. Among the carriers, solely fear of dying soon predicted non-compliance in recommended surveillance. Some non-carriers were still worried about their risk and had doubts about the validity of their genetic testing results predicting post-test colonoscopy.

100 years Lynch syndrome: what have we learned about psychosocial issues?

In the care of patients with Lynch Syndrome (LS), a range of psychosocial issues are encountered, which significantly affect patient outcomes. A brief historical background of 'psycho-onco-genetics' (the domain where psychology, oncology and genetics meet) in relation to LS is presented, followed by an overview of important psychosocial issues identified in the past 20 years. The identification of mismatch repair genes in 1993-1994 made possible genetic counseling and testing for patients who had cancer and for potentially high-risk relatives without cancer. At that time, concerns were raised about the potentially negative psychosocial impact of predictive genetic testing. Since 1993, a large number of studies have been conducted to investigate the possible psychosocial benefits and limitations of such testing. This article presents an overview of: the uptake of and motivations for genetic testing, its psychosocial impact (e.g. psychological adaptation, impact on risk perception and self-concept, and concerns about, and experiences of, genetic discrimination), psychological screening instruments, adherence to and decision-making about preventive strategies, family communication, lifestyle changes, reproductive technology utilization, and professional psychosocial support needs of members of families with LS. Finally, challenges for the future are discussed, including population screening and genomic testing.

Effects of hypothetical type 2 diabetes genetic testing on parents' efforts to prevent diabetes in children

OBJECTIVE

To examine the effect of hypothetical genetic susceptibility test results on diabetic parents' intention to prevent type 2 diabetes (T2D) in their children.

METHODS

Parents with T2D indicated their intention to prevent T2D in their youngest child at baseline and after a hypothetical positive and negative T2D genetic test result. We calculated mean/median "preventive intention scores" for each scenario and examined the association between parents' score change and parent/child characteristics.

RESULTS

A total of 63% of parents reported that their child had "almost no risk" or "slight risk" of developing T2D. Parents' median baseline preventive intention score was 8. It increased to 10 after a positive test result and decreased to 5 after a negative test result.

CONCLUSIONS

Negative T2D genetic susceptibility test results may decrease diabetic parents' intentions to prevent T2D for their children. Future research studies in a real-life clinical context should examine this phenomenon.

Patient compliance based on genetic medicine: a literature review

For this literature review, medical literature data bases were searched for studies on patient compliance after genetic risk assessment. The review focused on conditions where secondary or tertiary preventive options exist, namely cancer syndromes (BRCA-related cancer, HNPCC/colon cancer), hemochromatosis, thrombophilia, smoking cessation, and obesity. As a counterpart, patient compliance was assessed regarding medication adherence and medical advice in some of the most epidemiologically important conditions (including high blood pressure, metabolic syndrome, and coronary heart disease) after receiving medical advice based on nongenetic risk information or a combination of genetic and nongenetic risk information. In the majority of studies based on genetic risk assessments, patients were confronted with predictive rather than diagnostic genetic profiles. Most of the studies started from a knowledge base around 10 years ago when DNA testing was at an early stage, limited in scope and specificity, and costly. The major result is that overall compliance of patients after receiving a high-risk estimate from genetic testing for a given condition is high. However, significant behavior change does not take place just because the analyte is "genetic." Many more factors play a role in the complex process of behavioral tuning. Without adequate counseling and guidance, patients may interpret risk estimates of predictive genetic testing with an increase in fear and anxiety.

Perceived versus predicted risks of colorectal cancer and self-reported colonoscopies by members of mismatch repair gene mutation-carrying families who have declined genetic testing

People carrying germline mutations in mismatch repair genes are at high risk of colorectal cancer (CRC), yet about half of people from mutation-carrying families decline genetic counselling and/or testing to identify mutation status. We studied the association of quantitative measures of risk perception, risk prediction and self-reported screening colonoscopy in this elusive yet high-risk group. The sample of 26 participants (mean age 43.1 years, 14 women) in the Australasian Colorectal Cancer Family Registry were relatives of mutation carriers; had not been diagnosed with any cancer at the time of recruitment and had declined an invitation to attend genetic counselling and/or testing. A structured elicitation protocol captured perceived CRC risk over the next 10 years. Self-reported colonoscopy screening was elicited during a 45-minute semi-structured interview. Predicted 10-year CRC risk based on age, gender, known mutation status and family history was calculated using "MMRpro." Mean perceived 10-year risk of CRC was 31 % [95 % CI 21, 40], compared with mean predicted risk of 4 % [2, 7] (p < 0.001); this was independent of age and sex (p = 0.9). Among those reporting any medical advice and any screening colonoscopy (n = 18), those with higher risk perception had less frequent colonoscopy (Pearson's r = 0.49 [0.02, 0.79]). People who decline genetic testing for CRC susceptibility mutations perceive themselves to be at substantially higher risk than they really are. Those with high perceived risk do not undertake screening colonoscopy more often than those who perceive themselves to be at average risk.

Health behaviors in patients and families with hereditary colorectal cancer

It is estimated that 5 to 10% of all colorectal cancer (CRC) cases are attributed to a hereditary cause. The primary hereditary cancer syndromes that confer an increased risk for colorectal cancers are Lynch syndrome/hereditary nonpolyposis colorectal cancer (HNPCC) and familial adenomatous polyposis (FAP). Through genetic testing, health care providers can identify patients and families who carry gene mutations and subsequently are at a substantially greater risk for developing colorectal cancer than the general population. Genetic testing provides risk information not only about an individual patient, but also his or her biological relatives. A variety of risk-reduction behaviors (including screening, surgery, and health and lifestyle behaviors) have been examined in Lynch syndrome and FAP populations. The research indicates that screening behaviors are less than optimal, although the rates vary from study to study. Prophylactic colectomy is the primary course of treatment for individuals who test positive for a FAP mutation, but the results are inconclusive for cancer-unaffected Lynch syndrome mutation carriers. Although research suggests that the adoption of healthy lifestyles and behaviors (e.g., diet, physical activity, weight control, smoking cessation, limited alcohol consumption) could have a favorable impact on colon cancer burden, there is minimal data on how these behaviors may moderate cancer risk among those at risk of hereditary colon cancer. To date, we know very little about the actual health and lifestyle behaviors of those at risk of hereditary colon cancer. Genetic testing and counseling at risk individuals may resolve uncertainty about their personal and familial cancer risk and provide information to guide and personalize decisions about their future health care.

Changes in screening behaviors and attitudes toward screening from pre-test genetic counseling to post-disclosure in Lynch syndrome families

The purpose of this study was to examine colonoscopy adherence and attitudes toward colorectal cancer (CRC) screening in individuals who underwent Lynch syndrome genetic counseling and testing. We evaluated changes in colonoscopy adherence and CRC screening attitudes in 78 cancer-unaffected relatives of Lynch syndrome mutation carriers before pre-test genetic counseling (baseline) and at 6 and 12 months post-disclosure of test results (52 mutation negative and 26 mutation positive). While both groups were similar at baseline, at 12 months post-disclosure, a greater number of mutation-positive individuals had had a colonoscopy compared with mutation-negative individuals. From baseline to 12 months post-disclosure, the mutation-positive group demonstrated an increase in mean scores on measures of colonoscopy commitment, self-efficacy, and perceived benefits of CRC screening, and a decrease in mean scores for perceived barriers to CRC screening. Mean scores on colonoscopy commitment decreased from baseline to 6 months in the mutation-negative group. To conclude, adherence to risk-appropriate guidelines for CRC surveillance improved after genetic counseling and testing for Lynch syndrome. Mutation-positive individuals reported increasingly positive attitudes toward CRC screening after receiving genetic test results, potentially reinforcing longer term colonoscopy adherence.

Applying genomics to nutrition and lifestyle modification

Personalized nutrition aims to prevent the onset and development of chronic diseases by targeting dietary recommendations to an individual’s genetic profile. Gene–diet interactions that affect metabolic pathways relevant to disease risk are continuously being uncovered. Discoveries in the field of nutrigenomics demonstrate that some individuals may benefit from adhering to different dietary guidelines than others, depending on their genotype. Certain industries have already begun to capitalize on the anticipation that knowledge of genomic information could help prevent the risk of developing diseases. Although disclosure of genetic information has been associated with the adoption of positive health-related behaviors under certain circumstances, the effect of providing gene-based dietary advice on motivating adherence to favorable dietary changes is largely unknown.

Impact of genetic testing on endometrial cancer risk-reducing practices in women at risk for Lynch syndrome

OBJECTIVE

Due to the increased lifetime risk of endometrial cancer (EC), guidelines recommend that women with Lynch syndrome (LS) age ≥ 35 undergo annual EC surveillance or prophylactic hysterectomy (PH). The aim of this study was to examine the uptake of these risk-reducing strategies.

METHODS

The study population included women meeting clinical criteria for genetic evaluation for LS. Data on cancer risk-reducing behaviors were collected from subjects enrolled in two distinct studies: (1) a multicenter cross-sectional study involving completion of a one-time questionnaire, or (2) a single-center longitudinal study in which subjects completed questionnaires before and after undergoing genetic testing. The main outcome was uptake of EC risk-reducing practices.

RESULTS

In the cross-sectional cohort, 58/77 (75%) women at risk for LS-associated EC reported engaging in EC risk-reduction. Personal history of genetic testing was associated with uptake of EC surveillance or PH (OR 17.1; 95% CI 4.1-70.9). Prior to genetic testing for LS, 26/40 (65%) women in the longitudinal cohort reported engaging in EC risk-reduction. At one-year follow-up, 16/16 (100%) mismatch repair (MMR) gene mutation carriers were adherent to guidelines for EC risk-reduction, 9 (56%) of whom had undergone PH. By three-year follow-up, 11/16 (69%) MMR mutation carriers had undergone PH. Among women with negative or uninformative genetic test results, none underwent PH after testing.

CONCLUSIONS

Genetic testing for LS is strongly associated with uptake of EC risk-reducing practices. Women found to have LS in this study underwent prophylactic gynecologic surgery at rates comparable to those published for BRCA1/2 mutation carriers.

Individual-level factors in colorectal cancer screening: a review of the literature on the relation of individual-level health behavior constructs and screening behavior

OBJECTIVE

Compliance with colorectal cancer screening recommendations requires considerable conscious effort on the part of the individual patient, making an individual's decisions about engagement in screening an important contributor to compliance or noncompliance. The objective of this paper was to examine the effectiveness of individual-level behavior theories and their associated constructs in accounting for engagement in colorectal cancer screening behavior.

METHODS

We reviewed the literature examining constructs from formal models of individual-level health behavior as factors associated with compliance with screening for colorectal cancer. All published studies examining one or more constructs from the health belief model, theory of planned behavior, transtheoretical model, or social cognitive theory and their relation to screening behavior or behavioral intentions were included in the analysis.

RESULTS

By and large, results of studies supported the theory-based predictions for the influence of constructs on cancer screening behavior. However, the evidence base for many of these relations, especially for models other than the health belief model, is quite limited.

CONCLUSIONS

Suggestions are made for future research on individual-level determinants of colorectal cancer screening.

Lynch syndrome: barriers to and facilitators of screening and disease management

Background

Lynch syndrome is a hereditary cancer with confirmed carriers at high risk for colorectal (CRC) and extracolonic cancers. The purpose of the current study was to develop a greater understanding of the factors influencing decisions about disease management post-genetic testing.

Methods

The study used a grounded theory approach to data collection and analysis as part of a multiphase project examining the psychosocial and behavioral impact of predictive DNA testing for Lynch syndrome. Individual and small group interviews were conducted with individuals from 10 families with the MSH2 intron 5 splice site mutation or exon 8 deletion. The data from confirmed carriers (n = 23) were subjected to re-analysis to identify key barriers to and/or facilitators of screening and disease management.

Results

Thematic analysis identified personal, health care provider and health care system factors as dominant barriers to and/or facilitators of managing Lynch syndrome. Person-centered factors reflect risk perceptions and decision-making, and enduring screening/disease management. The perceived knowledge and clinical management skills of health care providers also influenced participation in recommended protocols. The health care system barriers/facilitators are defined in terms of continuity of care and coordination of services among providers.

Conclusions

Individuals with Lynch syndrome often encounter multiple barriers to and facilitators of disease management that go beyond the individual to the provider and health care system levels. The current organization and implementation of health care services are inadequate. A coordinated system of local services capable of providing integrated, efficient health care and follow-up, populated by providers with knowledge of hereditary cancer, is necessary to maintain optimal health.

Risk perception among Brazilian individuals with high risk for colorectal cancer and colonoscopy

Background

Risk perception is considered a motivating factor for adopting preventive behaviors. This study aimed to verify the demographic characteristics and cancer family history that are predictors of risk perception and to verify if risk perception is a predictor of colonoscopy adherence.

Methods

Individuals with a family colorectal cancer history as indicated by a proband with cancer were interviewed by telephone. They responded to a questionnaire covering demographic characteristics, colonoscopy history and four questions on risk perception. Tests of multiple linear regression and logistic regression were used to identify associations between dependent and independent variables.

Results

The 117 participants belonged to 62 families and had a mean age of 45.2 years. The majority of these individuals were female (74.4%) and from families who met the Amsterdam Criteria (54.7%). The average risk perception was 47.6%, with a median of 50%. The average population perception of individual risk was 55.4%, with a median of 50%. Variables associated with a higher risk perception were age, gender, religion, school level, income, and death of a family member. The variable predicting colonoscopy was receiving medical information regarding risk (odds ratio OR 8.40).

Conclusions

We found that family cancer history characteristics (number of relatives with cancer, risk classification) are associated with adequate risk perception. Risk perception does not predict colonoscopy in this sample. The only variable that predicted colonoscopy was receiving medical information recommending screening.

Colonoscopy use following mutation detection in Lynch syndrome: exploring a role for cancer screening in adaptation

Lynch syndrome (LS) is the most common inherited form of colorectal cancer. Mutation carriers can reduce the morbidity and mortality associated with colorectal cancer through colonoscopy. Theoretical models suggest that such health-related behaviors might also bring psychological benefits. This study assessed whether colonoscopy following mutation detection was associated with the levels of depressive symptoms. Data were obtained from a prospective family cohort study offering genetic services for LS. Participants completed questionnaires prior to the provision of services and 6 months post-receipt of mutation results. One hundred thirty-four (134) persons were identified to carry a mutation and completed both the questionnaires. Main outcome measures were depressive symptoms 6 months post-receipt of test results. Mutation carriers who did not complete a colonoscopy within the 6 months following receipt of results were six times (p < 0.01; odds ratio = 6.06) more likely to report depressive symptoms at a level of clinical importance post-receipt of test results compared to those who did undergo colonoscopy. Facilitating the expeditious use of colonoscopy following mutation detection may benefit newly identified mutation carriers by addressing the objective risks for cancer and moderating underlying emotional distress responses to genetic risk information. Furthermore, depressive symptoms may interfere with behavioral compliance in some patients, suggesting referral to mental health specialists.

Long-term compliance with endoscopic surveillance for familial adenomatous polyposis

AIM

The study assessed compliance of patients with familial adenomatous polyposis (FAP) with endoscopic surveillance.

METHOD

In this nationwide, cross-sectional study, individuals from FAP families registered with the Netherlands Foundation for the Detection of Hereditary Tumours were invited to complete a questionnaire on endoscopic screening experiences.

RESULTS

 A total of 328 individuals were eligible for the study of whom 85 were at risk for FAP, 108 had an intact rectum after a colectomy with ileorectal anastomosis (IRA), and 135 had had a pouch following a proctocolectomy with ileoanal anastomosis (IPAA). Based on medical record data, 20% of the at-risk group and 26% of the IRA-group were found to be undercompliant with surveillance advice which was associated significantly with perceived self-efficacy, use of sedatives during surveillance, pain after surveillance and low perceived benefits of surveillance (P < 0.05).

CONCLUSION

One in five individuals at risk for FAP and one in four with a retained rectum are undercompliant with screening advice. We recommend that sedatives should be patient-tailored for FAP individuals undergoing surveillance and that adequate pain medication be provided after endoscopy.

Health benefits and cost-effectiveness of primary genetic screening for Lynch syndrome in the general population

In current clinical practice, genetic testing to detect Lynch syndrome mutations ideally begins with diagnostic testing of an individual affected with cancer before offering predictive testing to at-risk relatives. An alternative strategy that warrants exploration involves screening unaffected individuals via demographic and family histories, and offering genetic testing to those individuals whose risks for carrying a mutation exceed a selected threshold. Whether this approach would improve health outcomes in a manner that is cost-effective relative to current standards of care has yet to be demonstrated. To do so, we developed a simulation framework that integrated models of colorectal and endometrial cancers with a 5-generation family history model to predict health and economic outcomes of 20 primary screening strategies (at a wide range of compliance levels) aimed at detecting individuals with mismatch repair gene mutations and their at-risk relatives. These strategies were characterized by (i) different screening ages for starting risk assessment and (ii) different risk thresholds above which to implement genetic testing. For each strategy, 100,000 simulated individuals, representative of the U.S. population, were followed from the age of 20, and the outcomes were compared with current practice. Findings indicated that risk assessment starting at ages 25, 30, or 35, followed by genetic testing of those with mutation risks exceeding 5%, reduced colorectal and endometrial cancer incidence in mutation carriers by approximately 12.4% and 8.8%, respectively. For a population of 100,000 individuals containing 392 mutation carriers, this strategy increased quality-adjusted life-years (QALY) by approximately 135 with an average cost-effectiveness ratio of $26,000 per QALY. The cost-effectiveness of screening for mismatch repair gene mutations is comparable to that of accepted cancer screening activities in the general population such as colorectal cancer screening, cervical cancer screening, and breast cancer screening. These results suggest that primary screening of individuals for mismatch repair gene mutations, starting with risk assessment between the ages of 25 and 35, followed by genetic testing of those whose risk exceeds 5%, is a strategy that could improve health outcomes in a cost-effective manner relative to current practice.

Consumers' views of direct-to-consumer genetic information

In this report, we describe the evolution and types of genetic information provided directly to consumers, discuss potential advantages and disadvantages of these products, and review research evaluating consumer responses to direct-to-consumer (DTC) genetic testing. The available evidence to date has focused on predictive tests and does not suggest that individuals, health care providers, or health care systems have been harmed by a DTC provision of genetic information. An understanding of consumer responses to susceptibility tests has lagged behind. The Multiplex Initiative is presented as a case study of research to understand consumers' responses to DTC susceptibility tests. Three priority areas are recommended for accelerated research activities to inform public policy regarding DTC genetic information: (a) exploring consumer's long-term responses to DTC genetic testing on a comprehensive set of outcomes, (b) evaluating optimal services to support decision making about genetic testing, and (c) evaluating best practices in promoting genetic competencies among health providers.

Outcomes of interest in evidence-based evaluations of genetic tests

Genetic tests are increasingly available for use in traditional clinical practice settings and through direct-to-consumer marketing. The need for evidence-based information and guidance on their appropriate use has never been more apparent. The independent Working Group of the Evaluation of Genomic Applications in Practice and Prevention Initiative commissions evidence-based reviews and develops recommendations to inform decision making surrounding the implementation of genetic tests and other applications of genomic technologies into clinical practice. A critical component of this analysis involves the identification and appropriate weighting of relevant health outcomes from genetic testing. Impacts of testing on morbidity and mortality are central considerations although research to document such outcomes can be challenging to conduct. In considering the broader impacts of genetic tests on the individual, familial and societal levels, psychosocial outcomes often take on increasing importance, and their systematic evaluation is a challenge for traditional methods of evidence-based review. Incorporating these types of outcomes in evidence-based processes is possible, however, and necessary to extract balanced and complete (or as complete as available data will allow) information on potential benefits and on potential harms. The framework used by the Evaluation of Genomic Applications in Practice and Prevention Working Group in considering, categorizing, and weighting health-related outcomes as applied to genomic technologies is presented here.

Patient responses to genetic information: studies of patients with hereditary cancer syndromes identify issues for use of genetic testing in nephrology practice

Advances in the genetic basis of kidney disease may mean that genetic testing is increasingly important in reducing disease morbidity and mortality among patients. However, there is little research examining patient responses to genetic information for Mendelian and common kidney diseases. Existing research on kidney and other hereditary cancer syndromes can inform three major issues relevant to the nephrology context as follows: (1) how patients understand their risk of disease after genetic counseling and testing, (2) their emotional responses to the information, and (3) their uptake of recommended risk-reducing strategies. Prior research suggests that genetic counseling and testing may improve patient understanding of genetics, but patients still might not fully understand the meaning of their results for disease risk. Genetic counseling and testing does not appear to result in long-term negative emotional effects among patients who carry mutations or those who do not. Finally, although genetic counseling and testing may improve adherence to recommended screening strategies, adherence varies substantially across different risk-reduction options. Previous research also suggests that computer-based interventions might be a useful adjunct to genetic counseling approaches. Examining whether and how these prior findings relate to the context of hereditary kidney disease is an important area for future research.

The behavioral response to personalized genetic information: will genetic risk profiles motivate individuals and families to choose more healthful behaviors?

This report describes the use of information emerging from genetic discovery to motivate risk-reducing health behaviors. Most research to date has evaluated the effects of information related to rare genetic variants on screening behaviors, in which genetic risk feedback has been associated consistently with improved screening adherence. The limited research with common genetic variants suggests that genetic information, when based on single-gene variants with low-risk probabilities, has little impact on behavior. The effect on behavioral outcomes of more realistic testing scenarios in which genetic risk is based on numerous genetic variants is largely unexplored. Little attention has been directed to matching genetic information to the literacy levels of target audiences. Another promising area for research is consideration of using genetic information to identify risk shared within kinship networks and to expand the influence of behavior change beyond the individual.

Communicating genetic and genomic information: health literacy and numeracy considerations

Genomic research is transforming our understanding of the role of genes in health and disease. These advances, and their application to common diseases that affect large segments of the general population, suggest that researchers and practitioners in public health genomics will increasingly be called upon to translate genomic information to individuals with varying levels of health literacy and numeracy. This paper discusses the current state of research regarding public understanding of genetics and genomics, the influence of health literacy and numeracy on genetic communication, and behavioral responses to genetic and genomic information. The existing research suggests that members of the general public have some familiarity with genetic and genomic terms but have gaps in understanding of underlying concepts. Findings from the limited research base to date indicate that health literacy affects understanding of print and oral communications about genetic and genomic information. Numeracy is also likely to be an important predictor of being able to understand and apply this information, although little research has been conducted in this area to date. In addition, although some research has examined behavior change in response to the receipt of information about genetic risk for familial disorders and genomic susceptibility to common, complex diseases, the effects of health literacy and numeracy on these responses have not been examined. Potential areas in which additional research is needed are identified and practical suggestions for presenting numeric risk information are outlined. Public health genomics researchers and practitioners are uniquely positioned to engage in research that explores how different audiences react to and use genomic risk information.

Considerations for the impact of personal genome information: a study of genomic profiling among genetics and genomics professionals

With the expansion of genomic-based clinical applications, it is important to consider the potential impact of this information particularly in terms of how it may be interpreted and applied to personal perceptions of health. As an initial step to exploring this question, we conducted a study to gain insight into potential psychosocial and health motivations for, as well as impact associated with, undergoing testing and disclosure of individual "variomes" (catalogue of genetic variations). To enable the collection of fully informed opinions, 14 participants with advanced training in genetics underwent whole-genome profiling and received individual reports of estimated genomic ancestry, genotype data and reported disease associations. Emotional, cognitive and health behavioral impact was assessed through one-on-one interviews and questionnaires administered pre-testing and 1-week and 3-months post-testing. Notwithstanding the educational and professional bias of our study population, the results identify several areas of research for consideration within additional populations. With the development of new and less costly approaches to genome risk profiling, now available for purchase direct-to-consumers, it is essential that genome science research be conducted in parallel with studies assessing the societal and policy implications of genome information for personal use.

Primary care providers' willingness to recommend BRCA1/2 testing to adolescents

Clinical practice guidelines discourage pediatric genetic testing for BRCA1/2 mutations due to a lack of timely medical benefit and psychosocial risk. Yet, some high risk families approach primary care providers (PCPs) about testing adolescents, and little is known about PCPs attitudes regarding these requests. We assessed recommendations for testing to a composite patient (a healthy 13-year-old female, mother is a BRCA mutation carrier) among 161 adolescent and family PCPs attending a national medical conference. Testing recommendations were measured with a multidimensional scale that assessed perspectives on informed consent, genetic counseling, and insurance coverage. PCPs expressed moderate willingness to recommend testing; surprisingly, 31% recommended adolescent testing "unconditionally." In multivariable regression modeling, recommendation was positively associated with higher clinical practice volume (P < .05) and greater frequency of ordering other pediatric genetic tests (P < .01). Despite a decade of clinical practice guideline advice to the contrary, experienced PCPs may still be inclined to recommend BRCA1/2 genetic testing to adolescents from high risk families. When paired with emerging data on the relative safety and efficacy of breast cancer genetic testing for high risk women and the advent of direct-to-consumer marketing of BRCA1/2 cancer genetic tests, professional societies may need to explore best practices to counsel high risk families and their PCPs about the potential risks and benefits of pediatric BRCA1/2 testing.

Family communication, genetic testing and colonoscopy screening in hereditary non-polyposis colon cancer: a qualitative study

OBJECTIVE

Genetic testing and colonoscopy is recommended for people with a strong history of colorectal cancer (CRC). However, families must communicate so that all members are aware of the risk. The study aimed to explore the factors influencing family communication about genetic risk and colonoscopy among people with a strong family history of CRC who attended a genetic clinic with a view to having a genetic test for hereditary non-polyposis colon cancer (HNPCC).

METHODS

Interviews were held with 30 people with a high familial risk of colon cancer. The transcripts were transcribed verbatim and analysed using Interpretative Phenomenological Analysis.

RESULTS

The family context, family history and perceptions about family duties and responsibilities were important motivators for communication about risk, genetic testing and colonoscopy and influenced participation in genetic testing and screening programmes. Participants reported usually communicating openly with their relatives about genetic risk and colonoscopy. Individuals felt a duty towards affected relatives and to their own children. The influence of the spouse and other relatives, particularly those affected by CRC, was also important. Colonoscopy was perceived to be embarrassing, unpleasant and sometimes painful. While there was sometimes anxiety about the result of the colonoscopy the results were usually reassuring.

CONCLUSIONS

The family context and the experience of the family history can have an impact on communication, genetic testing and screening in HNPCC and this should be explored during counselling. Some individuals might benefit from support in communicating with relatives about genetic risk. Ways of improving the individual's experience of colonoscopy should also be examined.

Colon cancer screening practices and disclosure after receipt of positive or inconclusive genetic test results for hereditary nonpolyposis colorectal cancer

BACKGROUND

Patients who receive conclusive genetic test results for hereditary nonpolyposis colorectal cancer (HNPCC) tend to adopt appropriate colorectal cancer screening behaviors and disclose their test results. However, little is known about the disclosure processes or screening behaviors of individuals who receive inconclusive genetic test results. This study compared endoscopy use and disclosure between individuals with positive and inconclusive genetic test results, within a year after results were received.

METHODS

Individuals with a personal history of cancer and suspected of having HNPCC participated in genetics education and counseling, underwent HNPCC testing, and received genetic test results (GCT) within a prospective cohort study. Demographic, psychosocial, and behavioral data were obtained from questionnaires and interviews completed before and after GCT.

RESULTS

Index cases with inconclusive genetic test results were less likely to screen within 12 months. Index cases who disclosed test results to children within 6 months were more likely to screen within 12 months, controlling for mutation status. Index cases with inconclusive genetic test results were less likely to share results with a healthcare provider within 6 months. Index cases who disclosed genetic test results to healthcare providers within 6 months were more likely to have endoscopy within 12 months.

CONCLUSIONS

Genetic test results and disclosure significantly affected colon cancer screening at 12-month follow-up. Interventions to improve adherence to colorectal cancer screening should consider increased education of those receiving inconclusive results and encourage disclosure to healthcare providers and family members.

Communication, encouragement, and cancer screening in families with and without mutations for hereditary nonpolyposis colorectal cancer: a pilot study

PURPOSE

Known and suspected mutation carriers for hereditary nonpolyposis colorectal cancer are advised to have colonoscopies every 1 to 2 years to detect colorectal cancer. Little is known about colonoscopy completion in families suspected of having hereditary nonpolyposis colorectal cancer but without identified mutations.

METHODS

This study examined the effect of communication and encouragement on colonoscopy in families with and without known mutations. Twenty-three respondents from 11 families with indeterminate genetic test results were matched with 23 respondents from 11 families with mutation-positive results. Hierarchical modeling examined the effects of relational characteristics on time since last colonoscopy in index cases and their first-degree relatives.

RESULTS

Nearly one fifth of respondents were not screening appropriately. Time since last screening did not differ according to family mutation status. However, respondents who communicated about risk and received encouragement to screen from a greater proportion of named family members, and those who had a greater proportion of named family members involved in both communication and encouragement were significantly more likely to have a shorter time interval since last colonoscopy.

CONCLUSION

Identifying patterns of interaction within at-risk families, regardless of gene mutation status, may be one avenue for promoting screening adherence.

Recommendations from the EGAPP Working Group: genetic testing strategies in newly diagnosed individuals with colorectal cancer aimed at reducing morbidity and mortality from Lynch syndrome in relatives

SUMMARY OF RECOMMENDATIONS

The Evaluation of Genomic Applications in Practice and Prevention (EGAPP) Working Group found sufficient evidence to recommend offering genetic testing for Lynch syndrome to individuals with newly diagnosed colorectal cancer to reduce morbidity and mortality in relatives. We found insufficient evidence to recommend a specific genetic testing strategy among the several examined.

RATIONALE

Genetic testing to detect Lynch syndrome in individuals with newly diagnosed colorectal cancer (CRC) is proposed as a strategy to reduce CRC morbidity and mortality in their relatives (see Clinical Considerations section for definition of Lynch syndrome). The EGAPP Working Group (EWG) constructed a chain of evidence that linked genetic testing for Lynch syndrome in patients with newly diagnosed CRC with improved health outcomes in their relatives. We found that assessing patients who have newly diagnosed CRC with a series of genetic tests could lead to the identification of Lynch syndrome. Relatives of patients with Lynch syndrome could then be offered genetic testing, and, where indicated, colorectal, and possibly endometrial, cancer surveillance, with the expectation of improved health outcome. The EWG concluded that there is moderate certainty that such a testing strategy would provide moderate population benefit.

ANALYTIC VALIDITY

The EWG found adequate evidence to conclude that the analytic sensitivity and specificity for preliminary and diagnostic tests were high.

CLINICAL VALIDITY

After accounting for the specific technologies and numbers of markers used, the EWG found at least adequate evidence to describe the clinical sensitivity and specificity for three preliminary tests, and for four selected testing strategies. These measures of clinical validity varied with each test and each strategy (see Clinical Considerations section).

CLINICAL UTILITY

The EWG found adequate evidence for testing uptake rates, adherence to recommended surveillance activities, number of relatives approachable, harms associated with additional follow-up, and effectiveness of routine colonoscopy. This chain of evidence supported the use of genetic testing strategies to reduce morbidity/mortality in relatives with Lynch syndrome. Several genetic testing strategies were potentially effective, but none was clearly superior. The evidence for or against effectiveness of identifying mismatch repair (MMR) gene mutations in reducing endometrial cancer morbidity or mortality was inadequate.

CONTEXTUAL ISSUES

CRC is a common disease responsible for an estimated 52,000 deaths in the United States in 2007. In about 3% of newly diagnosed CRC, the underlying cause is a mutation in a MMR gene (Lynch syndrome) that can be reliably identified with existing laboratory tests. Relatives inheriting the mutation have a high (about 45% by age 70) risk of developing CRC. Evidence suggests these relatives will often accept testing and increased surveillance.

The implications of genetic susceptibility for the prevention of colorectal cancer: a qualitative study of older adults' understanding

OBJECTIVE

To assess whether public understandings of inherited predisposition to colorectal cancer may undermine preparedness to respond to preventive messages.

METHODS

Structured in-depth interviews with 31 women and men, aged 50 years and over.

RESULTS

Most participants viewed genetic factors as prompts for taking preventive measures rather than as reasons for fatalism and inaction. They were optimistic about the potential benefits of new developments in cancer prevention and treatment.

CONCLUSIONS

There was little evidence of perceived genetic determinism in relation to colorectal cancer, but there were some significant misunderstandings about causes, prevention and treatment. These findings have important implications for public health communications about the contribution of genetics to cancer causation.