Diagnosis of gastric intraepithelial neoplasia by narrow-band imaging and confocal laser endomicroscopy

AIM:To evaluate the diagnosis of different differentiated gastric intraepithelial neoplasia (IN) by magnifica-tion endoscopy combined with narrow-band imaging (ME-NBI) and confocal laser endomicroscopy (CLE). METHODS:Eligible patients with suspected gastric IN lesions previously diagnosed by endoscopy in secondary hospitals and scheduled for further diagnosis and tratment were recruited for this study. Excluded from the study were patients who had liver cirrhosis, impaired renal function, acute gastrointestinal (GI) bleeding, coagulopathy, esophageal varices, jaundice, and GI post-surgery. Also excluded were those who were pregnant, breastfeeding, were younger than 18 years old, or were unable to provide informed consent. All patients had all mucus and bile cleared from their stom-achs. They then received upper GI endoscopy. When a mucosal lesion is found during observation with whitelight imaging, the lesion is visualized using maximal magnification, employing gradual movement of the tip of the endoscope to bring the image into focus. Saved images are analyzed. Confocal images were evaluated by two endoscopists (Huang J and Li MY), who were familiar with CLE, blinded to the related information about the lesions, and asked to classify each lesion as either a low grade dysplasia (LGD) or high grade dysplasia (HGD) according to given criteria. The results were compared with the final histopathologic diagnosis. ME-NBI images were evaluated by two endoscopists (Lu ZS and Ling-Hu EQ) who were familiar with NBI, blinded to the related information about the lesions and CLE images, and were asked to classify each lesion as a LGD or HGD according to the "microvascular pattern and surface pattern" classification system. The results were compared with the final histopathologic diagnosis. RESULTS: The study included 32 pathology-proven low grade gastric IN and 26 pathology-proven high grade gastric IN that were detected with any of the modalities. CLE and ME-NBI enabled clear visualization of the vascular microsurface patterns and microvascular structures of the gastric mucosa. The accuracy of the CLE and the ME-NBI diagnosis was 88% (95% CI:78%-98%) and 81% (95% CI: 69%-93%), respectively. The kappa coefficient of agreement between the histopathology and the in vivo CLE imaging was 0.755; between the histopathology and the in vivo CLE imaging was 0.615. McNemar's test (binomial distribution used) indicated that the agreement was significant (P < 0.05). When patients were diagnosed by MENBI with CLE, the overall accuracy of the diagnosis was 86.21% (95% CI:73%-96%), and the kappa coefficient of agreement was 0.713, according to McNemar's test (P < 0.05). CONCLUSION:Higher diagnostic accuracy, sensitivityand specificity of CLE over ME-NBI indicate the feasibility of these two techniques for the efficacious diagnostic classification of gastric IN.

Clinical efficacy and prognostic risk factors of endoscopic radiofrequency ablation for gastric low-grade intraepithelial neoplasia

BACKGROUND The use of radiofrequency ablation(RFA)has been reported in the treatment of gastric low-grade intraepithelial neoplasia(LGIN).However,its efficacy and prognostic risk factors have not been well analyzed.AIM To explore the efficacy and prognostic risk factors of RFA for gastric LGIN in a large,long-term follow-up clinical study.METHODS The clinical data of 271 consecutive cases from 198 patients who received RFA for treatment of gastric LGIN at the Chinese PLA General Hospital from October 2014 to October 2020 were reviewed in this retrospective study.Data on operative parameters,complications,and follow-up outcomes including curative rates were recorded and analyzed.RESULTS The curative rates of endoscopic RFA for gastric LGIN at 3 mo,6 mo,and 1-5 years after the operation were 93.3%,92.8%,91.5%,90.3%,88.5%,85.7%,and 83.3%,respectively.Multivariate analyses revealed that Helicobacter pylori(H.pylori)infection and disease duration>1 year had a significant effect on the curative rate(P<0.001 and P=0.013,respectively).None of patients had bleeding,perforation,infection,or other serious complications after RFA,and the main discomfort was postoperative abdominal pain.CONCLUSION RFA was safe and effective for gastric LGIN during long-term follow-up.H.pylori infection and disease course>1 year may be the main risk factors for relapse of LGIN after RFA.