OFR-4 Cytosponge-TFF3 for the detection of premalignant stomach: a cohort study from the BEST3 trial

IntroductionCytosponge is a pill on a string device that collects cells from the upper gastro-intestinal tract and is tested for intestinal metaplasia (IM) with the immunocytochemical TFF3 marker. Gastric IM (GIM) and atrophy (GA) are precursor lesions to gastric adenocarcinoma and require endoscopic surveillance. Non-invasive methods to detect gastric precancerous conditions are currently lacking. We aimed to evaluate the ability of Cytosponge-TFF3 to detect GIM/GA in the stomach.MethodsWe analysed data from 292 individuals who received a Cytosponge-TFF3 test and a subsequent endoscopy with gastric biopsies as part of the BEST3 trial (Fitzgerald et al. Lancet 2020). Patients with endoscopic or histological evidence of Barrett’s oesophagus (BO), IM at the gastro-oesophageal junction or with biopsies exclusively from fundic-type polyps were excluded. Endoscopic biopsies were assessed for the presence of atrophy or IM. The presence of GA/GIM was compared in TFF3 positive (TFF3+) and TFF3 negative (TFF3-) patients using Fisher’s exact test. P-values