BackgroundPostoperative mortality and morbidity rates are high in patients with obstructing colon cancer (OCC). Different treatment options have been evaluated over the years, mainly for left sided OCC. Optimising the preoperative health condition in elective colorectal cancer (CRC) treatment shows promising results. The aim of this study is to determine whether preoptimisation is feasible in patients with OCC, with a special interest/focus on right-sided OCC, and if, ultimately, optimisation reduces mortality and morbidity (stoma rates, major and minor complications) rates in OCC.MethodsThis is a prospective registration study including all patients presenting with OCC in our hospital. Patients with OCC, treated with curative intent, will be screened for eligibility to receive preoptimisation before surgery. The preoptimisation protocol includes; decompression of the small bowel with a NG-tube for right sided obstruction and SEMS or decompressing ileostomy or colostomy, proximal to the site of obstruction, for left sided colonic obstructions. For the additional work-up, additional nutrition by means of parenteral feeding (for patients who are dependent on a NG tube) or oral/enteral nutrition (in case the obstruction is relieved) is provided. Physiotherapy with attention to both cardio and muscle training prior surgical resection is provided. The primary endpoint is complication-free survival (CFS) at the 90 day period after hospitalisation. Secondary outcomes include pre- and postoperative complications, patient- and tumour characteristics, surgical procedures, total in hospital stay, creation of decompressing and/or permanent ileo- or colostomy and long-term (oncological) outcomes.DiscussionPreoptimisation is expected to improve the preoperative health condition of patients and thereby reduce postoperative complications.Trial registrationTrial Registry: NL8266 date of registration: 06-jan-2020.Study statusOpen for inclusion.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12876-023-02799-z.