[Update on colorectal cancer precursor lesions]

The adenoma-carcinoma sequence is currently well established, and therefore, the potential for adenomas to progress to colorectal cancer (CRC). In the last decade, there has been a change in the paradigm that considered these lesions as the only precursors of CRC and nowadays serrated polyps are also considered to have the potential for malignant transformation. The studies presented this year at the congress of the American Gastroenterological Association provide important information to improve the characterization of CRC precursor lesions, especially as regards their detection, prevalence and treatment and surveillance strategies. Notable among these studies were those focussing on evaluating the epidemiological characteristics of serrated polyps and those attempting to improve the quality of colonoscopy -with the ultimate aim of achieving greater detection of these precursor lesions- by evaluating colon cleansing, the polyp detection rate, withdrawal times, the use of endoscopic caps, narrow band imaging, high-definition endoscopy and, lastly, adequate endoscopic surveillance.