Sa1965 DEVELOPMENT AND VALIDATION OF A NEW CLASSIFICATION FOR IN VIVO DIAGNOSIS OF DUODENAL EPITHELIAL TUMORS WITH CONFOCAL LASER ENDOMICROSCOPY

Abstract

Endoscopic diagnosis for superficial non-ampullary duodenal epithelial tumors (SNADET) has not been established. Probe-based confocal laser endomicroscopy (pCLE: Cellvizio®) is an imaging technique to provide in vivo and real-time endomicroscopic analysis. To establish endoscopic diagnostic algorithm for SNADET, we developed and validated a new pCLE classification of SNADET based on the abnormal findings. Two cohorts of consecutive patients with SNADET were included. For the initial cohort (20 lesions from 16 patients, 16 adenomas and 4 carcinomas), pCLE scanning after intravenous administration of fluorescein was retrospectively evaluated. Abnormal findings such as dark epithelium, columnar cells irregularly extending to the lumen, fluorescein leakage and distorted crypt structure were determined in >1min of confocal video. For the second cohort (19 lesions from 9 patients, 16 adenomas and 3 carcinomas), the diagnostic yield of pCLE findings were prospectively evaluated by reference to the histopathology. Among non-neoplastic duodenal mucosa, duodenal adenomas and carcinomas in an initial cohort, frequencies of abnormal findings were 0% (0/20) vs. 87.5% (14/16) vs. 100% (4/4) for dark epithelium, 0% (0/20) vs. 56.3% (9/16) vs. 100% (4/4) for columnar cells irregularly extending to the lumen, 0% (0/20) vs. 56.3% (9/16) vs. 100% (4/4) for fluorescein leakage, 0% (0/20) vs. 6.3% (1/16) vs. 100% (4/4) for distorted crypt structure, respectively. The dark epithelium distinguished neoplastic lesions (adenomas and carcinomas) from non-neoplastic duodenal mucosa with a sensitivity of 90% and a specificity of 100%, while distorted crypt structure distinguished carcinomas from adenomas and non-neoplastic duodenal mucosa with a sensitivity of 100% and a specificity of 97.2%. In the second cohort, sensitivity and specificity of the dark epithelium for the diagnosis of neoplastic lesions was 73.4% and a specificity of 100%, while sensitivity and specificity of the distorted crypt structure for the diagnosis of carcinoma was 100% and 97.1%. The pCLE findings well correlated with histopathology of the SNADET. Especially, the dark epithelium and the distorted crypt structure were informative pCLE findings to predict neoplasia and cancer in the SNADET, respectively.