Optimising Colorectal Cancer Patient Pathways

Bowel cancer (colorectal cancer) is the 4th most common cancer in Scotland. Approximately 4,000 cases are diagnosed annually. Cancer-related deaths in Scotland are higher than other UK nations. Improving the early detection of bowel cancer, and therefore survival, is important. The majority of bowel cancers are diagnosed within secondary-care (colorectal surgery unit). Upon GP referral to secondary-care, patients provide stool samples which are analysed for microscopic blood (FIT; faecal immunohistochemical test). Patients with a single positive result are more likely to have bowel cancer (0.2% risk if no blood detected, but 8.4% if detected). A positive test triggers further investigation, either CT scan or colonoscopy depending on the result. Currently, colonoscopy and radiology services throughout Scotland are under significant pressure causing delays. Only 2% of patients referred to secondary-care are diagnosed with bowel cancer, and most colonoscopies performed do not yield significant findings. We have shown that performing two repeated FITs upon referral improves cancer pick-up rate (sensitivity) and reduces missed cancers. We successfully implemented this in NHS Lothian and contributed to national guidelines. Optimising allocation of investigations and therefore improving the detection-rate (specificity) may reduce colonoscopy demand, saving vital resources. NHS Lothian patients referred to secondary-care with symptoms concerning of bowel cancer will be included. \~1,000 included patients will undertake extra FIT tests in study whether changes in stool blood levels over time help better allocate investigations and improve test specificity. With these results, a new secondary-care pathway will be designed. Health economic analysis will determine costs and benefits of implementing a new pathway and the risks of missed cancers. The project also provides infrastructure to collect additional stool and blood samples to develop new tests that improve bowel cancer detection.

Sex

All

Minimum age

18 Years

Inclusion Criteria:

* Patients referred to the NHS Lothian USoC CRC pathway or an urgent referral with 'red-flag' symptoms, and with a positive FIT on referral will be included.
* Referred from start date of study, for up to 1 year

Exclusion Criteria:

* Two negative FITs on referral
* Patients referred with a palpable rectal or abdominal mass
* Previous history of CRC or IBD, or under polyp surveillance
* Known to have genetic hereditary condition predisposing patient to increased risk of CRC (e.g. Lynch, FAP, etc).

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