Although national guidelines recommend screening colonoscopy in individuals with familial colorectal cancer, its value is uncertain in the case of moderate-risk subjects. Furthermore, BSG and SIGN guidelines were revised in 2010 and 2011 respectively and it is unclear what impact this has had on the outcomes of screening. In the updated guideline, the moderate risk category has been subdivided into high and low moderate risk groups based on family history. High-moderate subjects are eligible for a screening colonoscopy at age 50 and a further scope every 5 years until the age of 75. The low moderate group should get a colonoscopy age 55 and no further scopes if normal. This contrasts with the previous advice to scope all moderate risk patients at the age of 35–40 and again aged 55.Methods
Retrospective audit of moderate risk subjects referred by the regional genetics service for screening colonoscopy between January 2000 and October 2017. Data collected included demographics, prevalence of adenomas, and high risk adenomas (>1 cm in size, villous histology or showing high grade dysplasia) on the initial screening colonoscopy. The number of referrals before and after local implementation of the guidelines in January 2012 was determined. Exclusion criteria included symptomatic patients, a personal history of CRC and those who did not attend for colonoscopy.Results
A total of 641 moderate risk subjects were referred for colonoscopy of which 179 were excluded. Of the remaining 462 subjects, 418 (90.5%) underwent complete colonoscopy up to the caecum, the rest had completion barium enema or CT colonography. There number of patients referred before and after the guideline update was 360 (mean age of 45.2 years, 53% female) and 102 (mean age 55.6 years, 50% female), respectively. The mean number of referrals per year reduced from 30 to 17 (p=0.002).Results
Detection of any adenoma increased from 10% (36 patients) to 18.6% (19 patients) after the guideline update (p=0.024) and detection of high-risk adenomas increased from 1.94% (7patients) to 3.92% (4 patients) after the guideline update (p=ns). No cases of malignancy were detected.Conclusions
Implementation of the revised BSG/SIGN guidelines for screening patients at moderate risk for familial colorectal cancer has resulted in a reduction in referrals for colonoscopy together with an increased yield of neoplasia.