Adjuvant chemotherapy is associated with improved overall survival in select patients with Stage II colon cancer: A National Cancer Database analysis

Background and Objectives Guidelines for Stage II colon cancer recommend adjuvant chemotherapy (AC) only for tumors with high-risk features, but long-term outcomes data are mixed. We aimed to determine if AC was associated with a survival benefit in this population. Methods Patients were identified from the National Cancer Database and included if they met the following criteria: diagnosis of Stage II colon cancer, surgery, survival data, and complete data on six high-risk features. The cohort of 57 335 patients was stratified by receipt of AC. Subgroup analysis was performed on patients under the age of 65 years with no comorbidities. Overall survival (OS) was the primary endpoint. Results An increasing number of high-risk features was associated with significantly decreased median OS. AC was associated with significantly increased OS for patients with 0, 1, 2, and >= 3 high-risk features. On subgroup analysis, receipt of AC was associated with a reduced risk of death (hazard ratio: 0.66; confidence interval: 0.59-0.74). For patients in the subgroup who had a T4 tumor, AC was associated with increased OS (92.7 vs. 83.6 months). Conclusions AC should be considered for all younger, healthy patients with Stage II colon cancer and may be associated with a survival benefit for patients with T4 disease.