Chemoprevention trials are currently under way to evaluate the effectiveness of various therapies for persons at risk of LS and FAP.[75,76] 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. 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 CRC 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 LS genetic counseling and testing. Studies have focused on whether individuals disclosed information about LS 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 LS predisposition and have comprised relatively small samples.
Research findings indicated that persons generally are willing to share information about the presence of a LS-predisposing mutation within their families.[78,79,80,81] Motivations for sharing genetic risk information include a desire to increase family awareness about personal risk, health promotion options and predictive genetic testing, a desire for emotional support, and a perceived moral obligation and responsibility to help others in the family.[79,80,81] Findings across studies suggested that most believed that LS 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.[78,79,80,81] In regard to informing second- and third-degree relatives, individuals may favor a cascade approach: for example, it was assumed that once a relative was given information about the family's risk for LS, he or she would then be responsible for informing his or her first-degree relatives.[78,79,80] 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.[78,79,80,82] In one study, persons who had undergone testing and were found to carry a LS-predisposing mutation were more likely to inform at least one second-degree or third-degree relative about their genetic test results, compared with persons who had received true negative or uninformative results.