Tu1464 Virtual Chromoendoscopy With I-SCAN for Real Time Diagnosis of Colorectal Cancer In Vivo

Virtual Chromoendoscopy With I-SCAN for Real Time Diagnosis of Colorectal Cancer In Vivo Helmut Neumann*, Michael Vieth, Martin Grauer, Dane Wildner, JuRgen Siebler, Markus F. Neurath Department of Medicine 1, University of Erlangen-Nuremberg, Erlangen, Germany; Institute of Pathology, Klinikum Bayreuth, Bayreuth, Germany Introduction: Colorectal cancer is the third most commonly diagnosed cancer in the world and colonoscopy still remains the gold standard for surveillance. i-scan was recently introduced as a new endoscopic imaging technique, enabling virtual chromoendoscopy during ongoing endoscopy that may allow better distinction and characterization of intestinal tissue in vivo. Aims: Main study objective was to assess the potential of i-scan for prediction of histology during screening colonoscopy for colorectal cancer. Material & Methods: Consecutive patients underwent screening or surveillance colonoscopy and were evaluated using a high-definition endoscope with i-scan capability. Circumscript lesions were examined by i-scan before taking biopsy specimens or performing polypectomy. i-scan images were graded according to the Kudo pit pattern classification and vascular changes and correlated with conventional histopathology in a prospective and blinded fashion. Results: i-scan yielded highquality images in all cases. Overall, 152 colorectal lesions were identified. 28% of lesions were neoplasic and 72% were non-neoplastic. Based on pit pattern and vasculare alterations i-scan could predict the presence of neoplastic changes with high sensitivity (95.2%), specificity (97.3%) and accuracy (96.7%). Positive and negative predictive values of i-scan for in vivo diagnosis of colorectal cancer were 98.2% and 93.0%, respectively. Conclusion: i-scan is a novel diagnostic tool which allows the real-time prediction of neoplasic changes with high accuracy. This may be of crucial importance in clinical practice and could lead to an optimized and rapid diagnosis of neoplasic changes during ongoing endoscopy.