STEP 2 REGISTRATION SECOND REGISTRATION (STEP 2) STEP 0: REGISTRATION (Optional) Patients with a primary colon or rectal cancer resection who are potentially eligible for S0820 may be pre-registered at Step 0; patients registered to Step 0 will appear on an institutional patient tracking report; patients registered to Step 0 are not registered to the S0820 protocol; to participate in S0820, patients must be registered to Step 1 after patient is consented and evaluation of eligibility; patients registered to S0820 at Step 0 continuing to Step 1 registration must use the same Southwest Oncology Group (SWOG) patient identification (ID) for registration to S0820 Step 1 STEP 1: REGISTRATION STEP II: Step 2 registration must be within 6 weeks of completing step 1 therapy STEP II: Any adverse event related to step 1 therapy must have resolved to grade 2 or less STEP II: Hemoglobin >= 8 g/dL (within 28 days prior to randomization to Step II) STEP II: Platelet count >= 75,000 cells/mm^3 (within 28 days prior to randomization to Step II) STEP II: Absolute neutrophil count >= 1000 cells/mm^3 (within 28 days prior to randomization to Step II) STEP II: Calculated creatinine clearance >= 30 mL/min (within 28 days prior to randomization to Step II) STEP II: Bilirubin =< 1.5 mg/dL (within 28 days prior to randomization to Step II) STEP II: SGPT (ALT) and SGOT (AST) < 2.5 times the upper limit of normal (within 28 days prior to randomization to Step II) Registration Step 1 Induction/Re-Induction: Registration Step 2 Post-Remission Therapy: PRIOR TO STEP 1 REGISTRATION PRIOR TO STEP 2 REGISTRATION STEP 2: RANDOMIZATION STEP 1 Patients must have discontinued radiation therapy prior to registering to Step 2 of the study and recovered from any adverse events associated with treatment; prior surgery must be >= 2 weeks from registration to Step 2 and patients must be fully recovered from post-surgical complications PRIOR TO STEP 1 REGISTRATION: PRIOR TO STEP 2 REGISTRATION: Within 2 weeks prior to screening step registration and within 4 weeks prior to treatment step registration: Leukocytes >= 3,000/mcL Within 2 weeks prior to screening step registration and within 4 weeks prior to treatment step registration: Absolute neutrophil count >= 1,500/mcL Within 2 weeks prior to screening step registration and within 4 weeks prior to treatment step registration: Platelets >= 100,000/mcL PRIOR TO STEP 1 REGISTRATION PRIOR TO STEP 2 REGISTRATION PRE-REGISTRATION (STEP 0) RANDOMIZATION (STEP 1) Patients must be registered to the first screening step (Step 0) for the National Cancer Institute (NCI)-MATCH trial (EAY131) STEP 1 (REGISTRATION) STEP 2 (REGISTRATION) STEP 1 REGISTRATION STEP 2 REGISTRATION PRIOR TO STEP 1 REGISTRATION: PRIOR TO STEP 2 REGISTRATION: PRIOR TO STEP 1 REGISTRATION PRIOR TO STEP 2 REGISTRATION PRIOR TO STEP ONE RANDOMIZATION: PRIOR TO STEP TWO RANDOMIZATION: STEP 1 REGISTRATION PRIOR TO STEP 2 REGISTRATION Financial clearance for proton therapy treatment prior step 2 registration