Metastatic colorectal cancer (mCRC) is a disease of older age, but there is a relative lack of knowledge about effects of chemotherapy in older patients as they are under-represented in clinical trials. | Randomized study comparing full dose monotherapy S-1 followed by irinotecan and reduced dose combination therapy S-1 oxaliplatin followed by S-1 irinotecan as initial therapy for older patients with metastatic colorectal cancer NORDIC 9