P-267 Spatially resolved detection of premalignant lesions and immune-infiltration in gastric endoscopic biopsies using multiplexed immunofluorescence and correlation with OLGA/OLGIM assessment

Gastric carcinogenesis (GC) is a multistep and multifactorial process the result of interplay between genetic susceptibility environmental factors. GC involves, in most cases, progression from normal mucosa through chronic gastritis, mucosal atrophy intestinal metaplasia to dysplasia neoplasia. The two diagnostic tools Operative Link on Gastritis Assessment (OLGA) Intestinal Metaplasia (OLGIM) are based histological assessment for identification precancerous lesions, however methodology with higher sensitivity required diagnosis small or incipient lesions. In this work, we simultaneously detected Sonic hedgehog protein (Shh) Trefoil factor 3 (Tff3) identify metaplasia, respectively, correlated infiltrating CD45+ cells, as well CD3 T-lymphocytes CD68 macrophages. Using Qupath performed an objective, reliable unsupervised cell phenotyping tissue segmentation multiplexed immunofluorescence. Tff3 was best biomarker premalignant lesions specificity around 90% compared OLGA/OLGIM same samples. Cases classified non-pathological score 0 showed lowest concordance (30%), mainly by isolated metaplastic foci mIF. Atrophy positively immune infiltration (p Helicobacter pylori < 0.05). combination immunostaining digital analysis increases study cascade adaptation microenvironment during gastric tumorigenesis. We expect translate tool into clinical practice our cancer cancer, improving early treatments.