Learning about hereditary cancer may influence an individual's self-concept, which otherwise represents a complex but stable cognitive structure. Recently, a 20-statement self-concept scale, with subscales related to stigma-vulnerability and bowel symptom-related anxiety, was developed for Lynch syndrome. We compared the performance of this scale in 591 mutation carriers from Denmark, Sweden and Canada. Principal component analysis identified two sets of linked statements-the first related to feeling different, isolated and labeled, and the second to concern and worry about bowel changes. The scale performed consistently in the three countries. Minor differences were identified, with guilt about passing on a defective gene and feelings of losing one's privacy being more pronounced among Canadians, whereas Danes more often expressed worries about cancer. Validation of the Lynch syndrome self-concept scale supports its basic structure, identifies dependence between the statements in the subscales and demonstrates its applicability in different Western populations.