BackgroundColorectal cancer is one of the most common malignancies in the Western world. Screening and detection of its precursor lesion, the adenoma could prevent development of colorectal cancer. Many studies have been done to evaluate the prevalence of colorectal cancer in different countries. In daily practice, it was noticed that colorectal cancer was rarely seen in patients of Turkish decent.AimTo evaluate the prevalence of colorectal cancer and adenoma in patients living in the Zaanstreek region, the Netherlands, and correlate these findings with ethnicity.Materials and methodsAll patients undergoing endoscopy of the colon and rectum during a period of 16 consecutive years in whom colorectal cancer and/or a polyp were diagnosed, were included in this study. All available histological data were retrieved in order to confirm the endoscopic diagnosis.ResultsIn the study period, 907 patients were diagnosed with colorectal cancer. Of these 13 (1.4%) were of Turkish descent (10 men and 3 women). The remaining 894 were authentic Dutch (473 men and 421 women). A total of 2,744 patients had one or more polyp(s) during endoscopy. There were 2,705 authentic Dutch (1,386 men, 1,319 women) and 39 Turkish patients (25 men, 14 women). There was no significant difference in gender in either of the groups.ConclusionColorectal cancer and colonic adenoma are rare in patients of Turkish descent living in the Zaanstreek region, the Netherlands.