BowelScreen FIT score prioritisation may be considered in future

BowelScreen does not currently prioritise for colonoscopy based on faecal immunochemical test (FIT) score, but this “may be considered at a future date”, a spokesperson has told the Medical Independent.

Personalised screening, as suggested in an article in Gut, was discussed
last year at a meeting of BowelScreen’s clinical advisory group (CAG), against the backdrop of reduced capacity due to Covid-19.

According to a commentary in Gut, ‘Personalised screening for colorectal cancer, ready for take-off’ (Kuipers and Grobbee), published online in 2020, FIT can both be used in a qualitative manner, leading to either a positive or negative result, or a quantitative manner resulting in the reporting of microgram faecal haemoglobin (Hb) per gram of faeces.

People screened with a FIT result above a prespecified threshold are referred for colonoscopy. A higher faecal Hb concentration is associated with a higher risk of advanced neoplasia. According to the article, most screening programmes use quantitative FIT, but the results are habitually reported in a dichotomised manner (ie, below or above a prespecified threshold).

“Such a dichotomised strategy subsequently misses out on countless possibilities in which the exact faecal Hb concentration could guide clinical decision-making.” One possibility was use of negative FIT results as a predictor of the risk of advanced neoplasia in following screening rounds.

The CAG’s meeting on 31 March 2020 heard that BowelScreen had suspended all invitations and reminders to participate. Four screening colonoscopy units were able to carry out some colonoscopies. “Circa 800 cases are currently due a colonoscopy. Some clients have chosen to cancel appointments.

“It is likely that these 800 cases could equate to approx 30 cancer cases,”
according to minutes.

Personalised screening was discussed at the CAG meeting on 18 May. The meeting heard of approximately 1,200 FIT positive cases in the system. There were two main sub-groups – firstly, clients pre-assessed for colonoscopy and who had their colonoscopy appointment postponed, and secondly, clients who had a positive FIT result and had not had a colonoscopy appointment.

In December 2020, colonoscopy units were operating at 40-to-70 per cent of normal capacity, stated the HSE. All FIT positive patients were “treated equally” and BowelScreen was considering insourcing and enrolling additional hospitals to provide colonoscopies.

“BowelScreen continues to screen at a reduced capacity, and continues to work with providers and host hospitals as they make local decisions on the level of follow-up screening procedures they can safely accommodate during the current wave of Covid-19,” stated the HSE on 20 January.