Winther SB, et al. - In older, vulnerable patients, researchers assessed reduced-dose combination chemotherapy vs full-dose monotherapy in the multicenter NORDIC9 trial. This trial was conducted in 23 Nordic oncology clinics, with patients 70 years of age or older and previously untreated metastatic colorectal cancer who were not eligible for full-dose combination chemotherapy. One hundred sixty patients (median age: 78 years; IQR 76-81) were randomly allocated to full-dose monotherapy (n=83) or reduced-dose combination chemotherapy (n=77) from March 9, 2015 to October 11, 2017. In older vulnerable patients with metastatic colorectal cancer, reduced-dose combination chemotherapy with S-1 and oxaliplatin was more efficacious and caused less toxicity vs full-dose S-1 monotherapy. For this population, reduced-dose combination chemotherapy may be a better treatment.