Exploratory Study of Rectal Mucus for Diagnosing Disease

The identification of patients with colorectal cancer is challenging as they present with a variable symptom profile and require invasive tests (colonoscopy) for diagnosis (through histological analysis of biopsies) and complimented by cross-sectional radiology, prior to commencement of treatment. The biopsy forms the basis of the diagnosis and management planning for a patient with colorectal cancer through the multidisciplinary team.
The biggest challenge currently faced in the management of colorectal cancer is the accurate identification of patients who present with various symptoms none of which are specific for bowel cancer. Currently the NICE referral guidelines are used to determine the appropriateness of referral pathway, i.e. Fast-Track/Two-Week Wait referral. A recent review of over 10000 referrals revealed a colorectal cancer diagnosis in 4.1% of referrals. Previous literature reports rates as high as 8%, but in series of cases with only 72-89% adherence to the referral guidance leading to at best 40% of all colorectal cases being diagnosed through this route. The remainder of colorectal cancers being diagnosed through the bowel cancer screening programme (NBCSP), non-two-week wait referrals and other processes such as emergency admissions. Inherently the Two-Week Wait pathway refers a large volume of "symptomatic patients" and it has become a "cancer exclusion pathway." Once cancer has been excluded, patients are often discharged back to General Practice, yet the patients often still have symptoms. The current Covid-19 pandemic has had a significant impact on the already pressed Two-Week pathway impacting on the reduction of endoscopic and radiological appointments available leading to delays in treatment. Each test performed in the diagnostic pathway has a significant financial, personal, and institutional resource profile.
It is our aim to develop a novel diagnostic device based upon the identification of genetic mutations and genomic alterations from material trapped in the rectal mucous layer allowing focused endoscopic assessment, confirmation/exclusion of cancer diagnosis from cross-sectional imaging in those unfit for endoscopic examination and identification of high-risk lesions (dysplasia). This would allow a greater triage, and focus colonoscopic services onto therapeutic procedures, improving overall care.