OBJECTIVES: I. Compare the survival and quality of life of patients with metastatic or recurrent colorectal cancer receiving palliative therapy with leucovorin/fluorouracil vs. continuous-infusion fluorouracil vs. ICI D1694. II. Compare the survival and quality of life of patients with stable or responding disease after 12 weeks of initial treatment randomized to receive 12 additional weeks of chemotherapy vs. no further treatment.