[How important is the quality of colonoscopy, considering the population screening for colorectal cancer?]

Colonoscopy is the reference standard for the detection of polyps and colorectal cancer (CRC). If during colonoscopy, all colorectal lesions are detected and completely removed, this individual will be long-term protected from CRC. The quality of the colonoscopy procedure is essential for an optimal protective effect. Recently published data of negative colonoscopies within the Polish Colonoscopy Screening Program, with a maximum follow-up of 17.4 years, demonstrated that high-quality colonoscopy was associated with a lower CRC incidence and mortality compared to low-quality colonoscopy. Colonoscopy quality was defined by completeness of colonoscopy, quality of the bowel preparation and number of detected colorectal lesions. These results suggest that the interval after a negative colonoscopy for the next screening might be safely prolonged, preventing unnecessary costs and risks for the patient. The quality of the initial colonoscopy is essential and a high quality will be fundamental for surveillance guidelines in the near future.