Objective: Previous data suggest that routine chromoendoscopy may increase detection rates of diminutive or flat lesions. The aim of this study was to evaluate the usefulness of chromoendoscopy in the ascending colon and cecum, where the incidence of diminutive or flat lesions is high.
Material and methods: Between June 2006 and September 2006, a total of 316 consecutive patients were prospectively enrolled in this study. The patients were randomly divided into two groups (control group: 158 patients, chromoendoscopy group: 158 patients). If the quality of bowel preparation was poor or cecal intubation was not achieved, the patient was excluded from the study. In the control group, the ascending colon and cecum were observed twice without chromoendoscopy. In the chromoendoscopy group, the cecum and ascending colon were reinspected following staining with indigocarmine solution after conventional examination of the cecum and ascending colon. Finally, a total of 151 and 149 patients were enrolled in the control and chromoendoscopy groups, respectively.
Results: The chromoendoscopy group differed significantly from the control group in the number of additionally detected polyps (control: 14 versus chromoendoscopy: 62, p<0.001) and in the number of patients with additionally detected polyps (control: 12 versus chromoendoscopy: 50, p<0.001). Multivariate analysis revealed that detection of polyps after indigocarmine spraying was independently associated with a high body mass index and older age (p = 0.045 and p = 0.006, respectively).
Conclusions: With chromoendoscopy using indigocarmine, more polyps can be detected in the ascending colon and cecum as compared with using conventional colonoscopy.