Lack of funding.

The overall aim of this study is to prospectively validate the superiority of the Immunoscore as a decision guidance for adjuvant chemotherapy in stage III colon cancer patients, in comparison to the conventional TNM-based high- or low-risk classification.

Inclusion Criteria:

• 18-75 years of age
• All sexes
• Histologically confirmed stage III carcinoma of the colon
• Medical need for an adjuvant chemotherapy
• Suitable to withstand the course of an adjuvant chemotherapy
• Written informed consent form (ICF) for participation in the study
• Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1

Exclusion Criteria:

• Neoadjuvant treatment
• Metastatic disease
• Pregnancy, breastfeeding or expectancy to conceive
• Disagreement of participants with reproductive potential to use contraception throughout the study period and for up to 180 days after the last dose of study therapy
• Uncontrolled or significant cardiovascular disease (myocardial infarction, uncontrolled angina, any history of clinically significant arrhythmias, QTc prolongation in males > 450 ms and > 470 ms in females, participants with history of myocarditis)
• Hepatitis B or C
• Human immunodeficiency virus (HIV)
• Immunodeficiency
• Allogeneic tissue or solid organ transplantation
• Systemic steroids or any other form of immunosuppressive therapy within 7 days prior to the first dose of study treatment
• Diagnosed and/or treated additional malignancy within 5 years of randomization, with the exception of curatively-treated basal cell or squamous cell carcinoma of the skin and/or curatively-resected in situ cervical and/or breast cancers
• Participants with serious or uncontrolled medical disorders
• Allergies and adverse drug reaction (history of allergy or hypersensitivity to study drug components, contraindications to any of the study drugs of the chemotherapy regimen)
• Other exclusion criteria: Prisoners or participants who are involuntarily incarcerated, participants who are compulsorily detained for treatment of either a psychiatric or physical (i.e. infectious disease) illness