Two‐tiered deep‐learning‐based model for histologic diagnosis of Helicobacter gastritis

Aims Helicobacter pylori (HP) infection is the most common cause of chronic gastritis worldwide. Due to the small size of HP and limited resolution, diagnosing HP infections is more difficult when using digital slides. Methods and Results We developed a two‐tier deep‐learning‐based model for diagnosing HP gastritis. A whole‐slide model was trained on 885 whole‐slide images (WSIs) with only slide‐level labels (positive or negative slides). An auxiliary model was trained on 824 areas with HP in nine positive WSIs and 446 negative WSIs for localizing HP. The whole‐slide model performed well, with an area under the receiver operating characteristic curve (AUC) of 0.9739 (95% confidence interval [CI], 0.9545–0.9932). The calculated sensitivity and specificity were 93.3% and 90.1%, respectively, whereas those of pathologists were 93.3% and 84.2%, respectively. Using the auxiliary model, the highlighted areas of the localization maps had an average precision of 0.5796. Conclusions HP gastritis can be diagnosed on haematoxylin‐and‐eosin‐stained WSIs with human‐level accuracy using a deep‐learning‐based model trained on slide‐level labels and an auxiliary model for localizing HP and confirming the diagnosis. This two‐tiered model can shorten the diagnostic process and reduce the need for special staining.