The follow-up of patients after colorectal cancer surgery mainly consists of blood CEA assessments. These blood assessments could be done at home and could be beneficial in terms of patients' well-being and societal cost-effectiveness. Capillary blood sampling can be an alternative to venipuncture in home based or decentralized surveillance as it can be performed by the patient themselves. Before home based capillary sampling can be implemented, feasibility, reliability, and satisfaction for serum CEA measurements has to be determined.