Patient and tumor characteristics may raise clinicians' awareness of familial colorectal cancer: a Norwegian population-based study.

ABSTRACT

BACKGROUND: The aim of this study was to identify patient and tumor characteristics that may be useful for clinicians in the identification of possible familial colorectal cancer (CRC). METHODS: Among 562 unselected, consecutively diagnosed colorectal cancer patients, 490 patients were included and divided into familial or sporadic CRC based on family history data collected by standardized patient interviews. Clinical data were collected from the patients' medical records. Patients were classified as familial CRC according to currently accepted family history criteria. Each patient was also classified according to Amsterdam II criteria and the 4th and 5th criteria in the Revised Bethesda Guidelines that address information on family history. Tumors were described by location and histopathology; 316 tumors were examined by molecular analyses. RESULTS: Right-sided colonic tumors and synchronous CRC tumors were associated with familial CRC, and patients with metachronous CRC or Lynch syndrome-related tumors were more likely to be classified as familial CRC. The patients' age at diagnosis did not differ between the groups. Other patient or tumor characteristics were not associated with familial CRC. CONCLUSION: CRC patients with right-sided colonic cancers, synchronous cancers and previous CRC and/or LS-related tumors were more likely to have familial CRC, and young age at diagnosis was not associated with familial CRC in these data. A detailed family history of colorectal cancer is essential in the identification of patients and families with familial CRC.