Interest in genetic testing among first-degree relatives of colorectal cancer patients

The present study examined colorectal cancer screening behaviors, risk perceptions, and willingness to receive genetic testing to determine colorectal cancer susceptibility.

We recruited 95 first-degree relatives of colorectal cancer patients, then conducted a brief telephone interview using a structured questionnaire that elicited information on sociodemographics, cancer screening behaviors, risk perceptions, and interest in genetic testing.

Among these high-risk individuals who were aged 40 years or older, only 31% reported fecal occult blood testing within the past year and 59% reported undergoing sigmoidoscopy or colonoscopy within the past 5 years. The majority of participants believed their relative risk of colorectal cancer was increased (68%). Eighty-four percent of the participants indicated that they would have a genetic test if one were available. Participants who believed that <50% of colorectal cancers were caused by heredity were more likely to be interested in genetic testing than were participants who believed that 50% or more of colorectal cancers were caused by heredity. Referral source, sociodemographic factors, clinical factors, and perceived personal risk were not significantly associated with interest in genetic testing.

Our results suggest that the demand for colorectal cancer susceptibility testing may be high among individuals with a family history of colorectal cancer. We also observed that a substantial number of first-degree relatives were not adhering to colorectal cancer screening guidelines. Accurate information on the genetic aspects of colorectal cancer and the benefits and limitations of genetic testing may help relatives of colorectal cancer patients make informed decisions about whether to undergo enhanced screening and genetic testing.