Establishing Absolute Iron Deficiency Anaemia Before Referring Patients to Colorectal Fast Track Clinics Can Help to Increase the Diagnostic Yield of the Bowel Cancer Screening Programme.

Although there are strict and specific guidelines for referring patients with iron deficiency anaemia (IDA) to fast track colorectal cancer (FT CRC) clinics for further assessment and investigation, patients with other types of anaemia are still referred by primary care physicians in the UK. Investigators aim was to find out whether this practice is correct, or if it is causing an overburden on colorectal clinics and endoscopy services. Investigators also want to find out whether true/absolute IDA has a higher predictive value for diagnosing colorectal cancer (CRC) compared to other types of anaemia and specific bowel symptoms.

Investigator's hypothesis was that patients with IDA are more likely to have CRC compared to patients with no anaemia or non-IDA anaemia. By confirming this hypothesis, Investigators can identify high risk patients from the population who can then be preferentially subjected to investigations mandated by guidelines. This strategy can help to increase the diagnostic yield of FT CRC clinics.

A retrospective cohort study was conducted from 2016-18 in a single busy district general hospital providing services to a population of 700,000 people.

In the study, patients with true IDA (low MCV and ferritin) were found to be more likely to have CRC compared to any other type of anaemia which confirmed the latest guidelines for management of IDA. Compared to symptoms, only the presence of a mass on abdominal examination and rectal examination was found to be more likely associated with cancer.

Physicians should be able to stratify patients based on blood indices when referring them to FT CRC clinics. Diagnostic yield of these clinics can be increased if clinicians strictly adhere to fast track guidelines and confirm true IDA before referring patients to clinic.