Introduction
Interest in Genetic Counseling and Testing for Hereditary Colorectal Cancer in the General Population and High-Risk Families
        Interest in genetic counseling and testing in the general population
        Interest in genetic counseling and testing among colorectal cancer patients and their close relatives
        Interest in genetic testing for children
Participation in Genetic Counseling and Testing for Hereditary Colorectal Cancer
        Lynch syndrome
        Familial adenomatous polyposis
Psychological Impact of Participating in Hereditary Colorectal Cancer Genetic Counseling and Testing
        Lynch syndrome
        Familial adenomatous polyposis
Psychosocial Aspects of Screening and Risk Reduction Interventions for Lynch Syndrome and FAP
        Endoscopic screening for Lynch syndrome
        Gynecologic cancer screening in Lynch syndrome
        Risk-reducing surgery for Lynch syndrome
        Colorectal screening for FAP
        Risk-reducing surgery for FAP
        Chemoprevention
        Family communication

Introduction

Psychosocial research in cancer genetic counseling and testing focuses on the interest in testing among populations at varying levels of disease risk, psychological outcomes, interpersonal and familial effects, and cultural and community reactions. It also identifies behavioral factors that encourage or impede surveillance and other health behaviors. Data resulting from psychosocial research can guide clinician interactions with patients and may include:

• Decision-making about risk-reduction interventions, risk assessment, and genetic testing.
• Evaluation of psychosocial interventions to reduce distress and/or other negative sequelae related to risk notification of genetic testing.
• Resolution of ethical concerns.

This summary will focus on psychosocial aspects of genetic counseling and testing for Lynch syndrome, familial adenomatous polyposis (FAP), and familial colorectal cancer, including those issues surrounding medical screening, risk-reducing surgery, and chemoprevention for those syndromes. Other hereditary colorectal cancer (CRC) syndromes such as Turcot, Muir-Torre and Peutz-Jeghers syndromes are not specifically addressed in this summary because they are very rare, and psychosocial research regarding these syndromes is lacking.

Interest in genetic counseling and testing for hereditary colorectal cancer has been highest in studies involving general population samples (Table 7A, 7B, 7C). Initial random-digit-dial surveys that addressed this topic [1-3] showed that more than 80% of respondents indicated at least some interest in having a genetic test for hereditary colorectal cancer, and 40% to 47% indicated that they would be very interested. One study [3] reported that interest in genetic testing decreased from 81% to 67% when respondents were informed that only 1% of the population was estimated to inherit a colorectal cancer–predisposing gene. A 2002 study that evaluated the participant's intention to have a genetic test within a specific time frame (e.g., within the next month and within the next 6 months) found substantially lower levels of interest.[4] Perceived risk of developing colorectal cancer was independently associated with greater interest in genetic testing across all studies. Other independent variables that were positively correlated with testing interest across studies included income, cancer worry, perceived benefits of testing, dispositional optimism and pessimism, and the perception that cancer runs in one’s family; perceived barriers of testing were negatively correlated with testing interest.

When respondents were asked about possible reactions if genetic testing showed that they were at high risk of colorectal cancer, the most common concerns included the lack of availability of preventive options, increased anxiety, and worry about cancer risks in family members, especially children.[2] Virtually no concern was expressed regarding the potential impact of such information on insurance or employment discrimination. This finding contrasts with findings in some other studies of individuals who have gone through genetic counseling before deciding about testing. Additionally, individuals with health insurance coverage were most likely to be willing to share test results with others, primarily their physicians.

Participants in these studies were drawn from the general population and were not selected for known colorectal cancer risk factors; their interest in genetic testing was based on answers to largely hypothetical questions. Some findings indicate that interest in genetic testing may be high in the general population; however, the apparent interest may be due in part to a lack of awareness about the risks and limitations of testing or the view that genetic testing is similar to other more routine medical tests.[2] Although these studies may help assess interest in genetic testing in the general population, it is possible that they overestimate the actual demand for such services.[5,6]

Studies of colorectal cancer patients and their unaffected relatives showed varying levels of interest in or intention to undergo hereditary colorectal cancer genetic testing (Table 7A, 7B, 7C). Participants in these studies were recruited through tumor registries or familial colon cancer registries,[7-10] oncology treatment centers,[11-14] and the community.[9,12-14] Study outcomes were reported as either testing interest or testing intention. Participants were not necessarily selected based on features that are characteristic of a hereditary colorectal cancer syndrome. Thus, when asking about intention or interest in genetic testing, most studies referred to testing in a general manner (e.g., testing for a hereditary colon cancer gene) rather than asking about testing for specific syndromes such as Lynch syndrome (also called hereditary nonpolyposis colorectal cancer [HNPCC]) or FAP. Some factors that were not consistently addressed in all studies (e.g., cost, test accuracy, or assuming that other relatives were gene mutation carriers) may account for some of the variability in findings regarding testing interest or intention.

In several studies, higher perceived risk and worry of developing colorectal cancer were correlated with interest in or intention to have testing.[7,8,11] Other correlates found in several studies included higher perceived risk and worry of developing colorectal cancer, higher education, greater family support, preference for making one’s own decision about testing, less advanced colorectal cancer, more frequent worries about colorectal cancer, belief that 50% or fewer of all colorectal cancers are hereditary, female gender, younger age, and ethnicity.[7,8,11-14] Participants in these studies cited many reasons for and against undergoing genetic testing. Perceived advantages of having information as a result of genetic testing included the ability to help other family members, especially children; engage in more informed health decision-making, particularly in regard to screening; plan for the future; and gain reassurance. Disadvantages included the possibility of insurance discrimination if one is found to carry a cancer-predisposing mutation, adverse psychological outcomes, and costs associated with testing.

A key difference between genetic testing for Lynch syndrome and FAP concerns the appropriateness of testing persons younger than 18 years. Genetic testing for adult-onset hereditary cancers is not recommended for minors because the medical and psychosocial benefits of such testing are not realized until adulthood.[18] Genetic testing for FAP, however, is presently offered to children with affected parents, often at the age of 10 to 12 years, when endoscopic screening is recommended. Because it is often necessary to diagnose FAP before age 18 years to prevent colorectal cancer and because screening and possibly surgery are warranted at the time an individual is identified as an APC mutation carrier, genetic testing of minors is justified in this instance.

Nonetheless, it is important to consider the implications of testing decisions with regard to issues of informed consent for both children and their parents. Parents have the legal authority to make medical decisions on behalf of their children; however, there are justifications for increasing minors’ involvement in decision-making about genetic testing as they mature and become more capable of making decisions about their own welfare.[18]

Studies conducted before the clinical availability of APC testing showed that most parents favored testing for FAP in early childhood.[19] In one study, 94% of FAP-affected adults indicated that children should be tested for FAP at birth, though 79% stated that this condition should not be discussed with children until at least age 10 years.[17] The majority of respondents wished to withhold information about FAP risk from their child for nearly a decade, suggesting that research is needed regarding the timing of disclosure of cancer genetic risk information to children.

There are an increasing number of studies examining the actual uptake of Lynch syndrome genetic counseling and testing (Table 8). Studies have included both colorectal cancer patients and unaffected, high-risk family members, recruited mainly from clinical settings and familial colon cancer registries. Most studies actively recruited participants for free genetic counseling and testing as part of research protocols.[10,20-26] Participation or uptake was defined at various points in the process, including genetic counseling before testing; provision of a blood sample for testing; and genetic counseling for disclosure of test results.

Participation in both pretest genetic counseling and posttest counseling for disclosure of results ranged from 14% to 59% across studies (Table 8). The wide range of uptake rates suggests that factors such as cost, test characteristics, and the context in which counseling and testing were offered may have influenced participants’ decisions. For example, among studies that offered free genetic counseling and testing in the context of a research protocol, counseling uptake ranged from 21% to 59% and testing uptake ranged from 36% to 59%.[10,20-22,24-26] The majority of those who had participated in a free pretest counseling or education session almost always followed through with genetic testing. Further research is needed to evaluate Lynch syndrome genetic counseling and testing participation in the clinical setting.

Although limited in number, these studies offer insight into why individuals from families at risk of Lynch syndrome decide to undergo or decline genetic counseling and testing. Participation in Lynch syndrome genetic counseling was associated with having children, having a greater number of relatives affected by colorectal cancer, and greater social support.[25] A study of colorectal cancer patients who had donated a blood sample for genetic testing also showed that those who intended to follow through with receiving results were more worried that they carried a Lynch syndrome-predisposing gene mutation, believed that testing would help family members, and more strongly endorsed the benefits and importance of having testing.[23] Factors associated with both counseling and testing uptake included having: children, a greater number of affected relatives, a greater perceived risk of developing colorectal cancer, and more frequent thoughts about colorectal cancer.[20-22,24-26]

Less is known about the characteristics of persons who decide to not undergo Lynch syndrome genetic counseling and testing. Studies have found that persons who declined counseling and testing reported to have a lower perceived risk for colorectal cancer,[20] to have fewer first-degree relatives affected with cancer,[26] to be less likely to have had a previous colonoscopy,[20] to have a college education,[21] to have previously participated in cancer genetics research,[21] or to be employed.[24] Psychological factors also may limit the uptake of genetic counseling and testing. Those who declined counseling and testing, especially women, reported lower perceived ability to cope with mutation-positive test results,[20] and were more likely to report having depressive symptoms.[21] Reasons cited for not seeking genetic counseling or testing have included concerns about potential insurance discrimination, how genetic testing would affect one's family, and how one would emotionally handle genetic test results.[26]

In contrast to the Lynch syndrome genetic counseling and testing uptake studies that have been conducted in the United States, findings from similar studies conducted in other countries may differ. A Finnish study found that 75% of individuals at risk of developing Lynch syndrome underwent genetic testing and counseling for disclosure of test results.[24] Being employed was the only factor that independently predicted test uptake. Fundamental differences between U.S. and Finnish health care systems may have accounted for the substantial differences in testing uptake in this study compared with similar ones conducted in the United States. In particular, the lower likelihood of health or life insurance discrimination in a European state such as Finland may have eliminated an important barrier to testing in that setting.[24]

The uptake for genetic testing for FAP may be higher than testing for Lynch syndrome. A study of asymptomatic individuals in the United States at risk for FAP who were enrolled in a colorectal cancer registry and were offered genetic counseling found that 82% of adults and 95% of minors underwent genetic testing.[28] Uptake rates close to 100% have been reported in the United Kingdom.[17] A possible explanation for the greater uptake of APC genetic testing is that it may be more cost-effective than annual endoscopic screening [29] and can eliminate the burden of annual screening, which must often be initiated before puberty. The opportunity to eliminate worry about potential risk-reducing surgery is another possible benefit of genetic testing for FAP. The decision to have APC genetic testing may be viewed as a medical management decision;[30] the potential psychosocial factors that may influence the testing decision are not as well studied for FAP as for other hereditary cancer syndromes.

The higher penetrance of APC mutations and earlier onset of disease also may influence the decision to undergo genetic testing for this condition, possibly due to a greater awareness of the disease and more experience with multiple family members being affected. Clinical observations suggest that children who have family members affected with FAP are very aware of the possibility of risk-reducing surgery, and focus on the test result as the factor that determines the need for such surgery.[28] It is important to consider the timing of disclosure of genetic test results to children in regard to their age, developmental issues, and psychological concerns about FAP. Children who carry an FAP mutation have expressed concern regarding how they will be perceived by peers, and might benefit from assistance in formulating an explanation for others that preserves self-esteem.[28]

Studies have examined the psychological status of individuals before, during, and after genetic counseling and testing for Lynch syndrome. Some studies have included only persons with no personal history of any Lynch syndrome-associated cancers,[31-34] and others have included both colorectal cancer patients as well as cancer-unaffected persons who are at risk for having a Lynch syndrome mutation.[35-39] Cross-sectional evaluations of the psychosocial characteristics of individuals undergoing Lynch syndrome genetic counseling and testing have indicated that mean pretest scores of psychological functioning for most participants are within normal limits.[35-37]

Several longitudinal studies have evaluated psychological outcomes before genetic counseling and testing for Lynch syndrome and at multiple time periods in the year following disclosure of test results. In general, findings from these studies suggested that mismatch repair mutation carriers may experience increased general distress,[33,38] cancer-specific distress,[31,32] or cancer worries [38] relative to their pretest measurements, within the period of time immediately following disclosure of their mutation status (e.g., 2 weeks to 1 month). Carriers often experienced significantly higher distress following disclosure of test results compared to individuals who do not carry a mutation previously identified in the family (noncarrier).[31-33,38] However, in most cases, carriers’ distress levels subsided during the course of the year after disclosure [33,38] and did not differ from pretest distress levels at 1 year postdisclosure.[31,32] Findings from these studies also indicated that noncarriers experienced a reduction or no change in distress up to a year following results disclosure.[31-33,38] A study that included unaffected individuals and colorectal cancer patients found that distress levels among patients did not differ between carriers and individuals who received results that were uninformative or showed a variant of unknown significance at any point up to 1 year posttest and were similar compared with pretest distress levels.[39]

Less is known about the long-term psychological impact of Lynch syndrome genetic counseling and testing beyond 1 year following notification of mutation carrier status. One study evaluated psychological outcomes up to 3 years after disclosure of mutation status.[31] Carriers’ and noncarriers’ 3-year mean scores on measures of depression, state anxiety, and cancer-specific distress were similar to scores obtained prior to genetic testing, with one exception: noncarriers’ cancer-specific distress scores showed sustained decreased posttesting, and were significantly lower compared with their baseline scores and with carriers’ scores at 1 year posttesting, with a similar trend observed at 3 years posttesting. In another study, 70 Lynch syndrome mutation carriers (including both cancer affected and unaffected persons) completed a cross-sectional survey between 6 months and 8.5 years after disclosure of test results; higher levels of cancer worry were associated with higher levels of perceived risk.[40]

Findings from some studies suggested that there may be subgroups of individuals at higher risk of psychological distress following disclosure of test results, including those who present with relatively higher scores on measures of general or cancer-specific distress before undergoing testing.[35-39,41] A study of colorectal cancer patients who had donated blood for Lynch syndrome testing found that higher levels of depressive symptoms and/or anxiety were found among women, younger persons, and nonwhites, as well as those with less formal education and fewer and less satisfactory sources of social support.[35] A subgroup of individuals who showed higher levels of psychological distress and lower quality of life and social support were identified from the same population; in addition, this subgroup was more likely to worry about finding out that they were Lynch syndrome mutation carriers and being able to cope with learning their test results.[36] In a follow-up report that evaluated psychological outcomes following disclosure of test results among both colorectal cancer patients as well as relatives at risk of having a Lynch syndrome mutation, a subgroup with the same psychosocial characteristics experienced higher levels of general distress and distress specific to the experience of having genetic testing within the year after disclosure, regardless of mutation status. Nonwhites and those with lower education had higher levels of depression and anxiety scores at all times compared with whites and those with higher education, respectively.[38] Other studies have also found that a prior history of major or minor depression, higher pretest levels of cancer-specific distress, having a greater number of cancer-affected first-degree relatives, greater grief reactions, and greater emotional illness-related representations predicted higher levels of distress from 1 to 6 months after disclosure of test results.[39,41] While further research is needed in this area, case studies indicate that it is important to identify persons who may be at risk for experiencing psychiatric distress and to provide psychological support and follow-up throughout the genetic counseling and genetic testing process.[42]

Studies also have examined the effect of Lynch syndrome genetic counseling and testing on cancer risk comprehension. One study reported that nearly all mutation carriers as well as noncarriers could accurately recall the test result 1 year after disclosure. More noncarriers than carriers correctly identified their risk of developing colorectal cancer at both 1 month and 1 year following result disclosure. Mutation carriers who incorrectly identified their colorectal cancer risk were more likely to have had lower levels of pretest subjective risk perception compared with those who correctly identified their level of risk.[33] Another study reported that accuracy of estimating colorectal and endometrial cancer risk improved following disclosure of mutation status in both carriers and noncarriers.[34]

Studies evaluating psychological outcomes following genetic testing for FAP suggest that some individuals, particularly mutation carriers, may be at risk for experiencing increased distress. In a cross-sectional study of adults who had previously undergone APC genetic testing, those who were mutation carriers exhibited higher levels of state anxiety than noncarriers and were more likely to exhibit clinically significant anxiety levels.[43] Lower optimism and lower self-esteem were associated with higher anxiety in this study,[43] and FAP-related distress, perceived seriousness of FAP, and belief in the accuracy of genetic testing were associated with more state anxiety among carriers.[44] In an earlier study, however, that compared adults who had undergone genetic testing for FAP, Huntington disease, and hereditary breast/ovarian cancer syndrome, FAP-specific distress was somewhat elevated within 1 week after disclosure of either positive or negative test results and was lower overall compared with the other syndromes.[30]

In a cross-sectional Australian study focusing on younger adults diagnosed with FAP (n = 88), aged 18 to 35 years, participants most frequently reported the following FAP-related issues for which they perceived the need for moderate-to-high levels of support or assistance: anxiety regarding their children’s risk of developing FAP; fear about developing cancer; and, uncertainty about the impact of FAP.[45] Seventy-five percent indicated that they would consider prenatal testing for FAP, 61% would consider pre-implantation genetic diagnosis and 61% would prefer that their children undergo genetic testing at birth or before age 10 years. A small proportion of respondents (16%) reported experiencing some FAP-related discrimination, primarily indicating that attending to their medical or self-care needs (e.g., time off work for screening, need for frequent toilet breaks, and physical limitations) may engender negative attitudes in colleagues and managers.

The psychological vulnerability of children undergoing testing is of particular concern in genetic testing for FAP. Research findings suggest that most children do not experience clinically significant psychological distress following APC testing. As in studies involving adults, however, subgroups may be vulnerable to increased distress and would benefit from continued psychological support. A study of children who had undergone genetic testing for FAP found that their mood and behavior remained in the normal range after genetic counseling and disclosure of test results. Aspects of the family situation, including illness in the mother or a sibling were associated with subclinical increases in depressive symptoms.[46] In a long-term follow-up study of 48 children undergoing testing for FAP, most children did not suffer psychological distress; however, a small proportion of children tested demonstrated clinically significant posttest distress.[47] Another study found that although APC mutation–positive children’s perceived risk of developing the disease increased after disclosure of results, anxiety and depression levels remain unchanged in the year following disclosure.[43] Mutation-negative children in this study experienced less anxiety and improved self-esteem over this same time period.

Recommendations for Lynch syndrome screening in persons at risk include colonoscopy every 1 to 2 years by age 20 to 25 years or 10 years earlier than the youngest age at diagnosis in the family, and annual endometrial cancer screening consisting of transvaginal ultrasound with endometrial sampling in women aged 30 to 35 years or starting 10 years earlier than the youngest age at diagnosis in the family.[48] These recommendations apply to persons who carry a Lynch syndrome-predisposing gene mutation, or who have a family history that is suggestive of Lynch syndrome in the absence of testing or the identification of a known mutation. Benefits of genetic counseling and testing for Lynch syndrome include the opportunity for individuals to learn about options for the early detection and prevention of cancer, including screening and risk-reducing surgery.

Studies suggest that many persons at risk for Lynch syndrome may have had some CRC screening before genetic counseling and testing, but most are not likely to adhere to Lynch syndrome screening recommendations. Among persons aged 18 years or older who did not have a personal history of colorectal cancer and who participated in U.S.-based research protocols offering genetic counseling and testing for Lynch syndrome, between 52% and 62% reported ever having had a colonoscopy before genetic testing.[20,22,49,50] Among cancer-unaffected persons who participated in similar research in Belgium and Australia, 51% and 68%, respectively, had ever had a colonoscopy before study entry.[34,51] Factors associated with ever having a colonoscopy before genetic testing included higher income and older age,[49] higher perceived risk of developing CRC,[51] higher education level, and being informed of increased risk for CRC.[50]

In a study of cancer-affected and cancer-unaffected persons who fulfilled clinical criteria for Lynch syndrome, 92% reported having had a colonoscopy and/or flexible sigmoidoscopy at least once before genetic testing.[52] Another study of unaffected individuals presenting for genetic risk assessment and possible consideration of Lynch syndrome, FAP, or APCI1307K genetic testing reported that 77% had undergone at least one screening exam (either colonoscopy, flexible sigmoidoscopy, or barium enema).

A few studies determined whether cancer-unaffected persons adhered to Lynch syndrome colonoscopy screening recommendations before genetic testing, and reported adherence rates of 10%,[34] 28%,[50] and 47%.[52]

Several longitudinal studies examined the use of screening colonoscopy by cancer-unaffected persons after undergoing testing for a known Lynch syndrome mutation.[34,49-51] These studies compared colonoscopy use before Lynch syndrome genetic testing to colonoscopy use within 1 year after disclosure of test results. One study reported that Lynch syndrome mutation carriers were more likely to have a colonoscopy compared with noncarriers and those who declined testing (73% vs. 16% vs. 22%), and that colonoscopy use increased among carriers (36% vs. 73%) in the year after disclosure of results.[50] Two other studies reported that carriers’ colonoscopy rates at 1 year after disclosure of results (71% and 53%) were not significantly different from rates before testing,[49,51] though noncarriers’ colonoscopy rates decreased in the same time period. Factors associated with colonoscopy use at 1 year after results disclosure included carrying a Lynch syndrome-predisposing mutation,[49-51] older age,[49] and greater perceived control over CRC. These findings suggest that colonoscopy rates increase or are maintained among mutation carriers within the year after disclosure of results and that rates decrease among noncarriers.

Two studies examined the level of adherence to published screening guidelines after Lynch syndrome genetic testing, based on mutation status. One study reported a colonoscopy adherence rate of 100% among mutation carriers.[34] Another study found that 35% of mutation carriers and 13% of noncarriers did not adhere to published guidelines for appropriate colorectal cancer screening;[49] in both groups, about one-half screened more frequently than published guidelines recommend, and one-half screened less frequently. There are no data available regarding variables that influence compliance with screening guidelines.

The longitudinal studies described above examined colorectal screening behavior within a relatively short period of time (1 year) after receiving genetic test results, and less is known about longer-term use of screening behaviors. A longitudinal study (n = 73) that examined psychological and behavioral outcomes among cancer-unaffected persons at 3 years following disclosure of genetic test results found that all carriers (n = 19) had undergone at least one colonoscopy between 1 and 3 years postdisclosure.[31] Ninety-four percent of carriers in one study stated an intention to have annual or biannual colonoscopy in the future; among noncarriers, 64% did not intend to have colonoscopy in the future or were unsure, and 33% intended to have colonoscopy at 5- to 6-year intervals or less frequently.[34] A cross-sectional study conducted in the Netherlands examined the use of flexible sigmoidoscopy or colonoscopy among persons with CRC, endometrial cancer, or a clinical or genetic diagnosis of Lynch syndrome during a time that ranged from 2 years to 18 years after risk assessment and counseling.[53] Eighty-six percent of Lynch syndrome mutation carriers, 68% of those who did not test or who had an uninformative Lynch syndrome genetic test result, and 73% of those with a clinical Lynch syndrome diagnosis were considered adherent with screening recommendations, based on data obtained from medical records. Participants also answered questions regarding screening adherence, and 16% of the overall sample reported that they had undergone screening less frequently than recommended. For the overall sample, greater perceived barriers to screening were associated with screening nonadherence as determined through medical record review, and embarrassment with screening procedures was associated with self-reported nonadherence. A second cross-sectional study, also conducted in the Netherlands, surveyed cancer-unaffected Lynch syndrome mutation carriers (n = 42) regarding their colorectal screening behaviors after learning their mutation status (range, 6 months–8.5 years). Thirty-one percent of respondents reported that they had undergone annual colonoscopy prior to Lynch syndrome genetic testing, and 88% reported that they had undergone colonoscopy since their genetic diagnosis (P < .001).[40]

A few studies have examined the use of screening for endometrial and ovarian cancers associated with Lynch syndrome. These studies have included relatively small numbers of women and suggest that screening rates for Lynch syndrome-associated gynecologic cancers are low before genetic counseling and testing. Two U.S. studies [22,52] reported that 14% of women with a family history of Lynch syndrome had undergone endometrial biopsy or 25% had undergone transvaginal ultrasound (TVUS) before genetic counseling and testing; among women who had seen a gynecologist in the preceding year, 50% had inadequate endometrial cancer screening.[52]

Some studies suggest that women with a clinical or genetic diagnosis of Lynch syndrome do not universally adopt intensive gynecologic screening.[31,54] In a Belgian study, 85% of female mutation carriers and 27% of noncarriers underwent TVUS within the year following disclosure of genetic test results.[34] One Australian longitudinal study examined gynecologic screening behaviors before testing, as well as 1 year after disclosure of results. They found that 30% of women had undergone TVUS and 7% had undergone an endometrial biopsy before testing.[51] Forty-seven percent of carriers and 10% of noncarriers reported having had a TVUS in the 12 months following test result disclosure, while 53% of carriers and 5% of noncarriers had undergone endometrial biopsy in that same period.

A cross-sectional study conducted in the Netherlands assessed gynecologic screening behaviors in Lynch syndrome mutation carriers, who were surveyed 6 months to 8.5 years after their genetic diagnosis. Seventeen percent of respondents reported that they had undergone gynecologic screening prior to undergoing genetic testing, and 69% reported they had undergone gynecologic screening since their genetic diagnosis (P < .001).[40] However, the screening interval and specific gynecologic tests were not described.

There is no consensus regarding the use of risk-reducing colectomy for Lynch syndrome, and little is known about decision-making and psychological sequelae surrounding risk-reducing colectomy for Lynch syndrome.

Among persons who received positive test results, a greater proportion indicated interest in having risk-reducing colectomy following disclosure of results as compared with baseline.[22] This study also indicated that consideration of risk-reducing surgery for Lynch syndrome may motivate participation in genetic testing. Before receiving results, 46% indicated that they were considering risk-reducing colectomy, and 69% of women were considering risk-reducing total abdominal hysterectomy (RRH) and risk reducing bilateral salpingo-oophorectomy(RRSO); however, this study did not assess whether persons actually followed through with risk-reducing surgery after they received their test results. Prior to undergoing Lynch syndrome genetic counseling and testing, 5% of cancer-unaffected individuals at risk for a mismatch repair mutation in a longitudinal study reported that they would consider colectomy, and 5% of women indicated that they would have an RRH and a RRSO, if they were found to be mutation-positive. At 3 years following disclosure of results, no participants had undergone risk-reducing colectomy.[31,51] Two women who had undergone a RRH before genetic testing underwent RRSO within 1 year after testing,[51] however, no other female mutation carriers in the study reported having either procedure at 3 years following test result disclosure.[31]

Less is known about psychological aspects of screening for FAP. One study of a small number of persons (aged 17–53 years) with a family history of FAP who were offered participation in a genetic counseling and testing protocol found that among those who were asymptomatic, all reported undergoing at least one endoscopic surveillance before participation in the study.[52] Only 33% (two of six patients) reported continuing screening at the recommended interval. Of the affected persons who had undergone colectomy, 92% (11 of 12 patients) were adherent to recommended colorectal surveillance. In a cross-sectional study of 150 persons with a clinical or genetic diagnosis of classic FAP or attenuated FAP (AFAP) and at-risk relatives, 52% of those with FAP and 46% of relatives at risk for FAP, had undergone recommended endoscopic screening.[55] Among persons who had or were at risk for AFAP, 58% and 33%, respectively, had undergone screening. Compared with persons who had undergone screening within the recommended time interval, those who had not screened were less likely to recall provider recommendations for screening, more likely to lack health insurance or insurance reimbursement for screening, and more likely to believe that they are not at increased risk for colorectal cancer. Only 42% of the study population had ever undergone genetic counseling. A small percentage of participants (14% to 19%) described screening as a “necessary evil,” indicating a dislike for the bowel preparation, or experienced pain and discomfort. Nineteen percent reported that these issues might pose barriers to undergoing future endoscopies. Nineteen percent reported that improved techniques and the use of anesthesia has improved tolerance for screening procedures.

When persons at risk of FAP develop multiple polyps, risk-reducing surgery in the form of subtotal colectomy or proctocolectomy is the only effective way to reduce the risk of colorectal cancer. Most persons with FAP can avoid a permanent ostomy and preserve the anus and/or rectum, allowing some degree of bowel continence. Studies of bowel function after subtotal colectomy show that patients average four to five stools per day in the immediate post-operative period, decreasing to three stools per day by 1 year post-surgery.[56]

With regards to behavioral or psychosocial outcomes, studies of risk-reducing surgery for FAP have found that general measures of quality of life have been within normal range, and the majority reported no negative impact on their body image.[57,58] However in one study, 29% who had undergone subtotal colectomy reported that increased stool frequency adversely affected their activities and 14% reported occasional liquid soiling.[56] Another study showed that 20% of those with good bowel function nonetheless reported fears about incontinence that affected their quality of life.[59]

Chemoprevention trials are currently under way to evaluate the effectiveness of various therapies for persons at risk of Lynch syndrome and FAP.[60,61] In a sample of persons diagnosed with FAP who were invited to take part in a 5-year trial to evaluate the effects of vitamins and fiber on the development of adenomatous polyps, 55% agreed to participate.[62] Participants were more likely to be younger, to have been more recently diagnosed with FAP, and to live farther from the trial center, but did not differ from nonparticipants on any other psychosocial variables.

Family communication about genetic testing for hereditary colorectal cancer susceptibility, and specifically about the results of such testing, is complex. It is generally accepted that communication about genetic risk information within families is largely the responsibility of family members themselves. A few studies have examined communication patterns in families who had been offered Lynch syndrome genetic counseling and testing. Studies have focused on whether individuals disclosed information about Lynch syndrome genetic testing to their family members, to whom they disclosed this information, and family-based characteristics or issues that might facilitate or inhibit such communication. These studies examined communication and disclosure processes in families after notification by health care professionals about a Lynch syndrome predisposition and have comprised relatively small samples.

Research findings indicated that persons generally are willing to share information about the presence of a Lynch syndrome-predisposing mutation within their families.[63-65] Motivations for sharing genetic risk information include a desire to increase family awareness about health promotion options and predictive genetic testing, as well as a perceived moral obligation and responsibility to help others in the family.[64,65] Findings across studies suggested that most believed that Lynch syndrome genetic risk information was shared openly within families; however, such communication was more likely to occur with first-degree relatives (e.g., siblings, children) rather than with more distant relatives.[63-65] In regard to informing more distant relatives, individuals tended to favor a cascade approach: for example, it was assumed that once a relative was given information about the family’s risk for Lynch syndrome, he or she would then be responsible for informing his or her first-degree relatives.[63-65] This cascade approach to communication was distinctly preferred in regard to informing relatives’ offspring, particularly those of minor age, and the consensus suggested that it would be inappropriate to disclose such information to a second-degree or third-degree relative without first proceeding through the family relational hierarchy.[63-66]

While communication about genetic risk was generally viewed as an open process, some barriers to doing so were reported across studies. Reasons for not informing a relative included lack of a close relationship and lack of contact with the individual; in fact, emotional rather than relational closeness seemed to be a more important determinant of the degree of risk communication. Disclosure seemed less likely if at-risk individuals were considered too young to receive the information (i.e., children), or if information about the hereditary cancer risk had previously created conflict in the family,[65] or if it was assumed that relatives would be uninterested in information about testing.[64] Prior existence of conflict seemed to inhibit discussions about hereditary cancer risk, particularly if such discussions involved disclosure of bad news.[65]

For most participants in these studies, the news that the pattern of cancers in their families was attributable to a Lynch syndrome-predisposing mutation did not come as a surprise,[63,64] as individuals had suspected a hereditary cause for the familial cancers or had prior family discussions about cancer. Identification of a Lynch syndrome-predisposing mutation in the family was considered a private matter but not necessarily a secret,[63] and many individuals had discussed the family’s mutation status with someone outside of the family. Knowledge about the detection of a Lynch syndrome-predisposing mutation in the family was not viewed as stigmatizing, though individuals expressed concern about the potential impact of this information on insurance discrimination.[63] Also, while there may be a willingness to disclose information about the presence of a mutation in the family, one study suggests a tendency to remain more private about the disclosure of individual results, distinguishing personal results from familial risk information.[66] In a few cases, individuals reported that their relatives expressed anger, shock, or other negative emotional reactions after receiving news about the family’s Lynch syndrome risk;[65] however, most indicated little to no difficulty in informing their relatives.[64] It was suggested that families who are more comfortable and open with cancer-related discussions may be more receptive and accepting of news about genetic risk.[65]

In some cases, probands reported feeling particularly obliged to inform family members about a hereditary cancer risk [65] and were often the strongest advocates for encouraging their family members to undergo genetic counseling and testing for the family mutation.[63] Some gender and family role differences also emerged in regard to the dissemination of hereditary cancer risk information. One study reported that female probands were more comfortable discussing genetic information than were male probands and that male probands showed a greater need for professional support during the family communication process.[64] Another study suggested that mothers may be particularly influential members of the family network in regard to communicating health risk information.[67] Mutation-negative individuals, persons who chose not to be tested, and spouses of at-risk persons reported not feeling as personally involved with the risk communication process compared with probands and other at-risk persons who had undergone genetic testing.[63]

Various modes of communication (e.g., in-person, telephone, or written contact) may typically be used to disclose genetic risk information within families.[63-65] In one study, communication aids such as a genetic counseling summary letter or Lynch syndrome booklet were viewed as helpful adjuncts to the communication process but were not considered central or necessary to its success.[64] Studies have suggested that recommendations by health care providers to inform relatives about hereditary cancer risk may encourage communication about Lynch syndrome [65] and that support by health care professionals may be helpful in overcoming barriers to communicating such information to family members.[66]

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