Tegafur-Uracil and Leucovorin or S-1 in Treating Patients With Stage III Colon Cancer That Has Been Completely Removed by Surgery

OBJECTIVES:

• Compare the disease-free survival of patients with stage III colon cancer treated with S-1 or tegafur-uracil and leucovorin after curative surgery .

OUTLINE: Patients are randomized to 1 of 2 treatment arms.

• Arm I: Patients receive oral tegafur-uracil and oral leucovorin 3 times daily on days 1-21. The treatment repeats 5 times every 5 weeks.
• Arm II: Patients receive oral S-1 twice daily on days 1-28. The treatment repeats 4 times every 6 weeks.

Biological samples are collected for gene expression analysis for identification of predictive markers.

DISEASE CHARACTERISTICS:

• Histologically confirmed adenocarcinoma of colon

• Stage III (T1-4, N1-3, M0) disease
• Has undergone surgical resection of the tumor within the past 8 weeks

PATIENT CHARACTERISTICS:

• ECOG performance status 0-1
• Able to take medications orally
• WBC ≥ 3,500/mm³ and < 12,000/mm³
• ANC ≥ 1,500/mm³
• Platelet count ≥ 100,000/mm³
• Hemoglobin ≥ 9.0 g/dL
• Total bilirubin ≤ 2.0 mg/dL
• AST/ALT ≤ 100 IU/L
• Creatinine ≤ 1.2 mg/dL
• No other active malignancies
• Must have none of the following comorbidities:

• Severe postoperative complications
• Uncontrollable diabetes mellitus
• Uncontrollable hypertension
• Myocardial infraction within 6 months
• Unstable angina pectoris
• Hepatocirrhosis
• Interstitial pneumonia, pulmonary fibrosis, or severe emphysema

PRIOR CONCURRENT THERAPY:

• No prior chemotherapy or radiotherapy for colon cancer
• No concurrent radiotherapy
• No concurrent biological response modifiers