Cytosponge for detecting abnormal cells in the oesophagus

The technology described in this briefing is Cytosponge. It is a minimally invasive oesophageal sampling device. The technology is used with a biomarker test to detect abnormal cells found in conditions such as Barrett's oesophagus.

The innovative aspects are the 'sponge on a string' pill for collecting oesophageal cell samples. The pill is used to collect cells from the oesophagus, which can then be tested by an antibody test to detect Trefoil Factor 3 (TFF3).

The intended place in the care pathway would be as a triage tool for an endoscopy to identify people at risk of oesophageal cancer.

The main points from the evidence summarised in this briefing are from 5 studies (2 systematic reviews, 1 randomised controlled trial and 2 cross-sectional studies). A review of 5 studies showed that Cytosponge was significantly more acceptable compared with the endoscopy procedure. Another review of 13 studies reported a pooled result of sensitivity of 81% and specificity of 91% using Cytosponge for detecting Barrett's oesophagus. Randomised controlled trial results showed that the estimated adjusted relative risk of detecting Barrett's oesophagus was 10.6 (95% confidence interval 6.0 to 18.8) for Cytosponge followed by an endoscopy compared with the standard care group that had endoscopy at 12-month follow up. Three included studies reported the sponge detached from the string, in a total of 4 people.

Key uncertainty around the evidence is that there is limited evidence from randomised controlled trials for the technology. One large trial included over 13,000 people from 109 GP surgeries, but Cytosponge uptake was low (around 25.6%).

The cost of using Cytosponge is £280 (excluding VAT), including the cost of the device and the assay test. The cost of the diagnostic endoscopy upper gastrointestinal tract procedure with biopsy is estimated to be £407.