Title: Patient acceptability and clinical effectiveness of combined Raman/FIT testing for colorectal cancer diagnosis in primary care
Funder: Health and Care Research Wales (Welsh Government)

Abstract: Background Colorectal cancer (CRC) is one of the commonest cancers in the Western world. Despite screening initiatives it continues to be diagnosed at late stages with attendant poor outcomes. There is a rising incidence of cancer in Wales and increasing numbers of patients are being referred on cancer diagnostic pathways due to new NICE referral guidelines. There is a pressing need to transform cancer referral pathways to allow secondary care to cope with the increasing demand for diagnostic testing. One way to reduce the referral burden would be a primary care-based diagnostic test. There is growing interest in the use of novel diagnostic markers in primary care to help triage patients with colorectal symptoms to aid referral decisions. These include the faecal immunochemical test (FIT) which detects haemoglobin in a faecal sample and the blood-based Raman-CRC spectroscopy test. Individually both tests have high negative predictive values (NPV over 98%) for CRC. Little work to date has explored attitudes and acceptability of these tests for cancer exclusion in primary care as a prudent alternative to hospital referral for invasive diagnostics. Without GP and patient endorsement then test introduction would be poorly utilised. Equally, new diagnostic tests have to show maximal accuracy for cancer confirmation or exclusion to permit pathway transformation through clinical effectiveness. Main aims 1)To qualitatively explore patient and health professional attitudes and experiences with combined Raman/FIT testing as an alternative to colonoscopy 2)To establish the NPV of Raman/FIT in a symptomatic primary care population. 3)To explore the feasibility of progression to a full trial. Investigation plan The study seeks to explore the acceptability of paired novel blood and faecal tests to diagnose colorectal neoplasia (cancer or polyps). The study will use qualitative methodology to theorise and hypothesise about test acceptability in various patient and GP groups through in-depth interviews and questionnaires. Secondly we will quantitatively establish the clinical effectiveness of the Raman/FIT test combination to diagnose CRC through a prospective observational cohort study. Interview groups are 1) those who receive the Raman/FIT test and are referred on the cancer pathway; 2) patients with more vague colorectal symptoms; 3) patients on a colonoscopy surveillance register with prior experience of invasive diagnostics; and 4) patients declining test participation from group 1. Interviews with GPs will explore confidence levels and barriers to implementation with Raman/FIT test at study end. Individual and combined Raman/FIT test performance will be examined as compared to final diagnosis in up to 800 eligible patients to establish sensitivity, specificity, area under curve and positive/negative predictive values. Patient compliance with providing blood and faecal samples will be measured as an indication of acceptability. Summary of benefits Patients with CRC would benefit from more appropriate and timely use of diagnostic resources, whilst patients without CRC will avoid the need for invasive diagnostic procedures. The NHS will benefit from a reduced pressure on their services and cost savings would be expected if the Raman/FIT combination were to be acceptable and implemented in the long term.


Research activity codes: 8.1 ORGANISATION AND DELIVERY OF SERVICES
Health categories: CANCER AND NEOPLASMS