The right time for colonoscopy

Colorectal cancer (CRC) continues to be one of the most frequently diagnosed GI malignancies worldwide, and fortunately, is potentially preventable. Colonoscopy remains as the most effective method for the diagnosis and treatment of preneoplastic lesions. Robust data over the past several years has emerged studying factors that are associated with high quality colonoscopy. Among these, the adenoma detection rate (ADR) is the most reliable parameter1 to predict the risk of interval cancer (ie, CRC diagnosed between 6 months and 10 years after colonoscopy) and, consequently, decrease the diagnosis of established malignancy. The ADR depends on multiple factors. A growing body of evidence suggests that the colonoscopy withdrawal time (CWT) is a crucial marker that correlates well with the ADR. Furthermore, this parameter can be monitored and modified to ultimately reach the optimal goals of an ADR higher than 20%. Thus, several studies have addressed its importance in the recent years. Initially, a 6 min CWT during a ‘negative colonoscopy’ (which means no abnormal findings translating in the absence of therapeutic procedures performed) was suggested. In recent years, however, this time threshold has increased to 9 min2. This change of paradigm is a consequence of the increasing knowledge regarding the clinically significant serrated polyps (CSSP). CSSP have a predisposition for the proximal colon and their macroscopic appearance is more subtle than traditional adenomas. Thereby, their detection requires a thorough inspection of the mucosa, which leads to an increased evaluation time focused particularly …