Use of Surfaced Enhanced Raman Spectroscopy to Distinguish Between Stimulated and Unstimulated Fibroblasts from Low Grade Dysplasia Barrett's Esophagitis Specimens

Background and aims: Confocal laser endomicroscopy (CLE) can provide real-time, microscopic visualization of the gastrointestinal mucosa, allowing an endoscopic approach to the histological evaluation of Barrett's esophagus-associated neoplasia, and may be helpful in guiding endoscopic therapy.At present, histopathological assessment is considered to be a gold standard and CLE cannot replace standard histopathology.The aim of this study was to evaluate (1) the accuracy of the probe based CLE for the differential diagnosis of nonneoplastic and neoplastic lesions in the esophagus and the stomach and (2) whether the use of CLE could help in determination of recurrent metaplasia/neoplasia in patients after endoscopic treatment of BORN.Methods: A single center, prospective, controlled and pathologist blinded (still ongoing) study consists of two parts.Part A: We enrolled patients with visible esophageal or gastric lesions and aimed to compare CLE with biopsies; Part B aimed to compare CLE with surveillance biopsies from neo-Z-line in patients after they had completed endoscopic treatment of BORN.Main outcomes were diagnostic accuracy of CLE vs. biopsies (definitive diagnosis was determined from resection specimen) (part A) and sensitivity of CLE in detection of recurrent intestinal metaplasia (IM) or neoplasia.Results: Forty-five patients have been included in the study (part A: 33, part B: 12 patients).Part A: We examined 37 lesions (31 esophageal, 6 gastric).Definitive diagnoses showed 20 malignant (14x adenocarcinoma, 6x squamous carcinoma) and 17 benign lesions.CLE diagnosis was correct in 23 (79%) lesions and incorrect in 6 lesions (21%), diagnosis based on biopsies was correct in 22 (81%) and incorrect in 5 lesions (19%).Sensitivity, specificity, and accuracy of biopsies for the accurate histological diagnosis were 86% CI 95 (69-96), 92% (67-98%) and 81% (66-96%); sensitivity, specificity, and accuracy of CLE for the accurate histological diagnosis were 83% (63-95%), 89% (65-98%) and 76% (62-92%), p= 0.12.Part B: Three patients (25%, 3/12) had recurrent IM in biopsies (CLE detected IM in one of these patients).One patient presented with recurrent IM on CLE only.Sensitivity and specificity of CLE for detection of recurrent IM was 60% (34-95%) and 90% (56-99%).One patient developed recurrent neoplasia (LGD not seen on CLE).Conclusion: CLE has high sensitivity and specificity in accurate histopathological diagnosis of esophageal and gastric visible lesions with diagnostic yield comparable with biopsies.Its role in detection of recurrent IM and neoplasia in patients after endoscopic treatment of BORN remains controversial.Further study with larger number of patients included is required to validate these results.Supported by a grant from Ministry of Health of the Czech Republic, No. 16-27648A.ClinTrial registration: NCT02922049.