Background: As genetic testing becomes more common and increasingly intertwined with medical care, the issues of genetic privacy and doctor-patient confidentiality are being examined. Hereditary non-polyposis colorectal cancer (HNPCC) is a genetic predisposition to colorectal and certain other cancers. Effective screening that can prevent colorectal cancer is an important incentive for genetic testing.
Methods: A survey regarding the duty to warn family members of the risks associated with an HNPCC-causing mutation was mailed to 227 participants in the Ontario Familial Colon Cancer Registry (OFCCR). To our knowledge, the opinions of patients on this subject have not been reported previously in the literature. Responses were analysed quantitatively using the SAS system and qualitatively by the review of written comments.
Results: Completed surveys were returned by 105 participants, with a response rate of 46.3%. The majority felt a personal responsibility to warn relatives, but there was no significant agreement that doctors or genetic counsellors should have a duty to warn relatives without a patient's permission.
Conclusions: Patients undergoing genetic testing for HNPCC generally understand that relatives could benefit from being informed of genetic risk, but may not be willing or able to inform each family member. Healthcare professionals should engage patients in a discussion of familial implications before genetic testing. An agreement should be formulated regarding which of the relatives should be informed. Patients should be encouraged to personally disseminate the information, given the unrealistic burden on practitioners to perform this task and patients' preference for control over the information.