The goal of this study is to learn about the epigenetic and genetic regulation (microRNA/mRNA) of colorectal polyps and their evolvement as polyps and to colorectal cancer. Furthermore, the study aims at investigating whether certain epigenetic features, linked to polyps and/or cancer are traceable in blood samples. The main questions the study aims to answer are: 1. Are there specific microRNA/mRNA that are expressed in different types of polyps and cancers and their respective stages? 2. Is microRNA/mRNA expression in polyps and cancer traceable in blood from the same patient? 3. Is the intestinal microbiata correlated with colorectal polyps and cancer and their microRNA/mRNA expression? Type of study: clinical trial Participant population Participants consist of patients undergoing a scheduled colonoscopy where a polyp or cancer is discovered. Healthy controls, with normal colonoscopy findings will be enrolled. Biopsies will be obtained from polyps/cancers and from normal surrounding intestinal mucosa. Biopsies will be obtained from defined intestinal locations from healthy controls. Blood samples will be collected from all participants. Researchers will compare microRNA/mRNA and microbiota in patients with polyps/cancers and their respective stages as well as healthy controls. Comparisons include biopsies and blood samples.