ASPIRIN Trial Belgium

Inclusion Criteria: * Patients 45 years and older with histologically confirmed adenocarcinoma of the colon * Patients must have TNM stage that is one of the following: pT3-4; N0-2 and M0, or pT1-2 and N1-2 (Union for International Cancer Control (UICC) stage II and III) (in case of \>1 tumour: more advanced tumour is stage II or III) * Patients must have completed surgical resection (R0) (both laparoscopic and open surgery) within 12 weeks of randomization Exclusion Criteria: * Patients with rectal cancer (defined as tumour within 15 cm from the anal verge) * Patients currently taking oral anti-coagulants or use of LMWH or use of DOACs * Patients currently taking (low-dose) acetylsalicylic acid or other anti-aggregantia for any reason * Patients with a history of bleeding disorders or active gastric or duodenal ulcers * Patients currently taking high dose systemic glucocorticoids (≥ 30 mg predniso(lo)n or equivalent) * Patients with (suspected) (non-) polyposis syndrome (FAP/AFAP, MAP, Lynch syndrome) * Patients with \>100 polyps of the colon or a known hereditary syndrome of the colon in a first degree family member * Allergy or intolerance to salicylates * Patients with local or distant recurrent disease * Previous malignancies other than CIN or SCC with a disease free survival less than 5 years * Presence of any psychological, familial, sociological or geographical condition potentially hampering compliance with the study protocol and follow-up schedule; those conditions should be discussed with the patient before registration in the trial