Family based colorectal cancer screening in a district hospital.

Colorectal cancer (CRC) screening using family history to define a group at increased risk is gaining support. Three hundred and ninety six subjects aged over 25 with at least one first degree affected relative have been screened using a single slide, immunological faecal occult blood test (FOBT), and family history data to select the highest risk group. Compliance was 64.9% but was significantly better if contact was made within one year of diagnosis of the index relative (75% v 62.1%, chi 2 = 5.7, p < 0.05). Twelve subjects (13.2%) of those who had a colonoscopy) bearing adenomas have been detected, three of which were at high risk of malignant transformation. No cancers have been diagnosed. Most subjects undergoing screening were less than 55 years of age (67.8%). These accounted for most colonoscopies (68.1%) but only one large adenoma was diagnosed in this group. The FOBT was particularly useful, enabling the detection of five large adenomas. Family based CRC screening is practical in a district hospital setting. Although labour intensive, it meets a population demand and can detect significant numbers of adenomas. Screening, even in those at moderately increased risk, could be focused on the older age groups, probably those aged over 40.