Introduction The 2-week wait pathway was designed to decrease the time from presentation to primary care with “red flag” symptoms of suspected cancer to review by a specialist for diagnosis or exclusion of cancer. Within our tertiary referral centre 968 colonoscopies per year are required to satisfy the demand for the 2-week wait at the expense of other services. We sought to determine yields of colorectal cancer found at colonoscopy in reference to original red flag symptoms in order to select the most efficacious primary investigation based upon presenting symptoms.

Method Electronic records were retrospectively analysed. All patients who went through the 2-week wait system for suspicion of colorectal cancer in 2013 found to have colorectal cancer at colonoscopy were included. Patients not undergoing colonoscopy as first investigation were excluded. The splenic flexure was deemed within the range of a flexible sigmoidoscope.

Results 2950 referrals were made. 968 colonoscopies were performed as the primary investigation. 35 patients were found to have colorectal cancer. No patients referred with rectal bleeding and another symptom had a tumour outside the range of a flexible sigmoidoscope. Eighty percent of tumours proximal to the splenic flexure were suitable for CT diagnosis alone.

Conclusion Our data supports the use of flexible sigmoidoscopy alone as an initial investigation for patients presenting with rectal bleeding with or without additional colorectal symptoms within our local population. Patients with anaemia (without bleeding) or change in bowel habit (without bleeding) may be investigated with CT colonography alone; colonoscopy may then be used selectively prior to surgery.

Disclosure of interest None Declared.