Introduction The BSG guidelines on colorectal cancer (CRC) screening recommend that the minimum age to cease surveillance colonoscopy is 75 years. The decision to continue surveillance should then be based on individual patient factors. Currently, there is an increasing demand on endoscopy services due to the introduction of screening programmes and initiatives to increase accessibility. We aim to evaluate the diagnostic yield and complication rate of surveillance colonoscopy in the over 75-age group.

Method A prospectively collected database of patients at GWH Swindon was interrogated and a consecutive cohort of patients undergoing surveillance colonoscopy for a history of polyps between 11/7/2011 and 6/7/2014 was identified. Patients <75 years, undergoing flexible sigmoidoscopy or colonoscopy for other indications, and those with a previous history of CRC were excluded. Local databases and the electronic patient record were used to obtain further information, including surveillance period, history of CRC, the number and size of polyps seen on colonoscopy, the number of polyps biopsied/retrieved, histology results, quality of each colonoscopy (degree of pain caused, limited colonoscopy/ poor bowel preparation), complication events, and follow up arrangements after colonoscopy. The final cohort comprised 74 patients. The primary outcome was significant adenoma yield (i.e. >1 cm) per annum surveillance. Secondary outcomes included complication rates, quality of colonoscopies, proportion of polyps investigated and accordance with BSG guidelines.

Results 1) Polyp, adenoma and significant adenoma yield per annum surveillance was 0.37%, 0.33% and 0.17% respectively. Only 2 patients developed CRC over 225 years of polyp surveillance.

2) 13.5% experienced significant pain.

3) 52.7% of surveillance colonoscopies were incomplete or had poor bowel preparation.

4) 80.6% of polyps were biopsied or retrieved.

5) No patient was found to have post-procedure bleeding or perforation.

6) Of 44 patients analysed, 25 patients (56.8%) had inappropriate surveillance colonoscopy according to BSG guidelines. Eighteen (41%) had surveillance earlier than was appropriate.

Conclusion Our service evaluation suggests that polyp surveillance in elderly patients does not result in a high adenoma/polyp yield; procedures are often suboptimal due to high rates of incomplete procedures and can cause significant pain. BSG guidelines were not followed accurately. This may expose patients to further harm and waste limited resources. It therefore may be more beneficial for endoscopy departments to reduce the number of elderly individuals to whom they offer surveillance or improve compliance with the BSG guidelines. These strategies may decrease demand without resulting in an increase in the incidence of significant neoplastic disease.

Disclosure of interest None Declared.