Inclusion Criteria:  Histologic diagnosis of carcinoma of the colon or rectum Undergone complete surgical resection of the primary tumor within 3 months prior to enrollment.  Pathologic stage II or III  Stage II patients must be microsatellite stable (MSS) and/or mismatch repair (MMR)-proficient. Stage III patients are eligible regardless of microsatellite instability (MSI) or MMR status. Eastern Cooperative Oncology Group (ECOG) performance status ≤ 2. No clinical contraindication to adjuvant chemotherapy.  Exclusion Criteria:  Received prior systemic anti-cancer therapy. Pregnant or breastfeeding at time of enrollment. Prior history and treatment for any invasive cancer within the past 5 years, with the exception of non-melanoma skin cancer Has a known history of an inherited genetic condition associated with an increased risk of colorectal cancer, with the exception of Lynch Syndrome in Stage III patients. MMR deficient tumor or germline MMR deficiency (Lynch Syndrome) with Stage II colorectal cancer. Prior stem cell transplant.