ThTP4.6 Which FIT level is fit for purpose?

Abstract

Abstract Aims To assess the diagnostic performance of faecal immunochemical test (FIT) in patients referred under the two week-wait (2WW) pathway and to test colorectal cancer (CRC) detection thresholds. Methods All patients referred under the 2WW pathway for a study period of 2 months were identified; referring symptoms, FIT levels, investigations and final diagnosis were collected via the electronic patient records. Exclusion criteria were patients who were not under the 2WW pathway, patients without FIT, those that declined or unfit for further investigations. Data was anonymized and analysed using the SPSS software. Results 438 patients were referred to the colorectal team during the study period, 335 patients (157 males and 178 females) met the inclusion criteria, age range 25-93 years, mean age 69.33 years (SD 12.66). 14 patients had a final diagnosis of colorectal cancer. All 14 patients had a FIT >6.9 (p 0.012), that was also the case with a FIT of 10 and above (p 0.002) which had a stronger association, FIT test 11 and above, 15 and above and 20 and above being the positive threshold detected 13 of 14 patients with CRC with a p value 0.008, 0.002 and 0.001 respectively. Conclusions Our data shows that a FIT threshold of 10 and above detected all patients with CRC and even a slight increase of the threshold to 11 missed 7.1% (1/14) of patients with CRC. Hence patients with ‘slightly positive FIT’ should be considered for further investigations if appropriate.