RESUMEN
<p><b>OBJECTIVE</b>To investigate the association between the morphological features of biopsy-diagnosed high grade intraepithelial neoplasia in the gastric mucosa and the postoperative pathology.</p><p><b>METHODS</b>Fifty-one patients with biopsy-diagnosed high grade intraepithelial neoplasia in the gastric mucosa were retrospectively analyzed. Thirty-three patients underwent surgery. The morphology of lesions under endoscopy and histopathological findings of the surgical specimens were investigated.</p><p><b>RESULTS</b>Of the 51 patients, 43 had superficial lesions similar to early gastric cancer under endoscopy, 8 were similar to advanced carcinoma. In the 33 surgical cases, high grade intraepithelial neoplasia of gastric mucosa was confirmed on postoperative pathological examination in 13 (39.4%) patients, adenocarcinoma was identified in the remaining 20 patients (60.6%), including 14 early gastric cancers and 6 advanced carcinomas. Thirteen cases with high grade intraepithelial neoplasia confirmed postoperatively were superficial elevated or flat lesions less than 20 mm.</p><p><b>CONCLUSIONS</b>Patients with biopsy-diagnosed high grade intraepithelial neoplasia in the gastric mucosa have a high risk of cancer. Thus aggressive follow-up and appropriate surgical interventions are recommended to avoid misdiagnosis.</p>