The Role Of Narrow Band Imaging In Diagnosis Of Gastrointestinal Tumors

Aims: To investigate diagnostic efficacy of targeted biopsy under the guidance of magnifying endoscopy with narrow band imaging(NBI,M-NBI,MNTB),diagnostic efficacy of NBI International Colorectal Endoscopic(NICE)classification in diagnosis of colorectal polyps and diagnostic efficacy of M-NBI in diagnosis of deep submucosal colorectal cancers(d SMC).Methods: This study prospectively collected 211 gastric lesions of suspected cancerous tissues diagnosed with MNTB and endoscopic forceps biopsy(EFB)and diagnostic efficacy of the two methods were compared.Meanwhile,486 colorectal lesions with NICE real-time diagnosis were collected and diagnostic efficacy of NICE classification in diagnosis of colorectal adenomas was calculated.Potential databases were searched to identify eligible studies about accuracy of M-NBI in diagnosis of d SMC.Diagnostic efficacy of M-NBI were pooled and were compared with that of magnifying chromoendoscopy(M-CE)in diagnosis of d SMC.Results: The accuracy,sensitivity,and specificity of MNTB were 75.4%(68.9–80.9%),72.7%(95%CI: 64.9–79.4%),82.5%(95%CI: 69.6–90.8%)and the accuracy of MNTB was higher than EFB(68.2%,95%CI: 61.4–74.4%,P=0.048).The real-time diagnostic accuracy,sensitivity,specificity of NICE classification were 87.9%(95%CI: 84.5-90.6),90.6%(95%CI: 87.1-93.2),77.7%(95%CI: 68.2-85.0)respectively and94.3%(95%CI: 91.5-96.2),96.2%(95%CI: 93.4-97.9),85.3%(95%CI: 74.8-92.1)under high confidence diagnosis.We identified 17 studies investigating diagnostic efficacy of M-NBI in diagnosis of d SMC.The pooled sensitivity,specificity and the area under summary receiver operating characteristic curves(AUC)in diagnosing d SMC were 74%(95%CI: 66-81%),98%(95%CI: 94-99%),and 0.91(95%CI: 0.88-0.93)for M-NBI.The pooled sensitivity,specificity and AUC were 84%(95%CI: 77-89%),97%(95%CI: 94-99%),and 0.97(95%CI: 0.95-0.98)for M-CE.M-NBI had lower sensitivity(P < 0.01)than M-CE with similar specificity(P = 0.32).Conclusion: MNTB had a higher diagnostic efficacy than EFB in the diagnosis of cancerous lesions.Chinese endoscopists can gain promising diagnostic accuracy in diagnosing colorectal neoplasia,especially when endoscopists made real-time diagnosis under high confidence level.M-NBI and M-CE had a comparable specificity in diagnosing d SMC,but the sensitivity of M-NBI was relatively lower than that of MCE.