Testing for colorectal cancer: a focus on FIT technology

Approximately 41,000 people are diagnosed with colorectal cancer (CRC) in the UK each year.¹ The prognosis is better in those with early-stage cancerous lesions or advanced adenomas (the pre-cancerous stages), with over 90% of cases being treated successfully following early detection. Diagnosing CRC is a complex process, typically starting with patients reporting to their GP with symptoms, subsequent referral for a gastroenterology consultation, a colonoscopy investigation and biopsy confirmation from histopathology.

To address reports that relative cancer survival rates are lower in the UK compared with other European countries, rapid diagnostic and treatment pathways were proposed as part of the 2000 National Health Service (NHS) Cancer Plan. This included an urgent 14-day referral pathway (known as the ‘two-week wait’) for an out-patient gastrointestinal (GI) consultation for patients presenting to their GP with ‘Red Flag’ symptoms.^2,3 This pathway continues in secondary care where patients are investigated, and treatment commences within 62 days of the out-patient GI consultation.⁴

To refer patients with suspected CRC selectively in a primary care setting is immensely challenging. Patients present to their GP with a range of symptoms including weight loss, abdominal pain, unusual bowel motions, rectal bleeding and anaemia. Although these are often considered to be key risk factors for CRC, such symptoms are also indicative of more common conditions, resulting in a low positive predictive value.⁵