Colorectal cancer is one of the most frequent cancers in the Western world. Forty-five percent of symptomatic patients have metastatic disease. The overall prevalence of adenoma in an asymptomatic... Show moreColorectal cancer is one of the most frequent cancers in the Western world. Forty-five percent of symptomatic patients have metastatic disease. The overall prevalence of adenoma in an asymptomatic population is 25-30% at the age of 50 years and approximately two-thirds of all colonic polyps are adenomatous. Around 95% of CRCs evolve from an adenomatous polyp or sessile serrated lesion (SSL). Only 5% of all adenomatous polyps progress to CRC. To reduce both the incidence and mortality rate of CRC, a national bowel screening program started in January 2014. This thesis focussed on improving clinical care for patients with colorectal neoplasms. From identifying high risk persons/families through the national screening program to modifying a surgical technique to a minimal invasive organ-preserving technique for removal of colorectal neoplasms to the treatment of metastatic colorectal cancer. All studies are based on clinical questions arise from the daily practice. And is therefore also applicable in daily practice. Show less