DIAGNOSIS OF SUPERFICIAL NON-AMPULLARY DUODENAL EPITHELIAL TUMORS USING MAGNIFIED ENDOSCOPY WITH NARROW-BAND IMAGING

Aims:

Endoscopic diagnosis to differentiate between low grade adenoma (Vienna category 3, C3) and high grade adenoma/intramucosal carcinoma (C4/5) among superficial non-ampullary duodenal epithelial tumors (SNADET) is important to judge the appropriate treatment. Using magnified endoscopy with narrow-band imaging (MNBI), we have previously extracted 8 MNBI combinations of mucosal and vascular patterns and reported that the presence of multiple combinations within a lesion is suggestive of C4/5 (sensitivity 91%, specificity 100%) (APDW 2017). However, inter-observer agreement of 8 combinations was not satisfactory. The aim of this study was to establish an easier MNBI diagnostic approach for SNADET.

Methods:

This was a retrospective image evaluation study. MNBI images of 106 SNADETs (C3: 16 lesions, C4/5: 90 lesions) were individually evaluated by 3 endoscopists blinded to histology. Identified MNBI combinations were reviewed and combinations with a high concordance were extracted. Using the selected combinations, another 55 SNADETs (C3: 18 lesions, C4: 38 lesions) were individually evaluated by 3 endoscopists. The sensitivity, specificity, accuracy for diagnosing C4/5 by MNBI was evaluated.

Results:

Four MNBI combinations (network, intrastructural vessel, white opaque substance, unclassified) showed high inter-observer concordance. Using these 4 MNBI combinations, the numbers of combination identified within a lesion showed moderate inter-observer concordance (kappa statistic: 0.59). When a lesion showed 2 or more MNBI combinations or an unclassified pattern, the diagnosis for C4/5 showed a sensitivity of 76%, specificity of 67%, accuracy of 72%.

Conclusions:

MNBI has the ability and potential to diagnose duodenal C4/5 lesions. However, the universality and accuracy still requires improvement.