Vaccine Therapy and Chemotherapy With or Without Tetanus Toxoid Compared With Chemotherapy Alone in Treating Patients With Metastatic Colorectal Cancer

DISEASE CHARACTERISTICS: Histologically confirmed metastatic colorectal adenocarcinoma No clinically active CNS metastases PATIENT CHARACTERISTICS: Age: 18 and over Performance status: ECOG 0-1 Life expectancy: More than 6 months Hematopoietic: Lymphocyte count at least 1,000/mm^3 Granulocyte count at least 1,500/mm^3 Platelet count at least 100,000/mm^3 Hemoglobin at least 10 g/dL Hepatic: Bilirubin less than 1.5 times upper limit of normal (ULN) AST/ALT less than 3 times ULN (5 times ULN if liver metastases present) Alkaline phosphatase less than 3 times ULN (5 times ULN if liver metastases present) No hepatocellular dysfunction No cirrhosis Renal: Creatinine less than 2.5 mg/dL Cardiovascular: No uncontrolled coronary artery disease No symptomatic congestive heart failure Pulmonary: No uncontrolled chronic obstructive lung disease Gastrointestinal: No unsolved bowel obstruction or subobstruction No uncontrolled Crohn's disease No ulcerative colitis No concurrent chronic diarrhea Immunologic: HIV negative No immunocompromised patients No diagnosis of altered immune function, including: Lupus erythematosus Sjogren's syndrome Scleroderma Myasthenia gravis Goodpasture's disease Addison's disease Hashimoto's thyroiditis Active Graves' disease No known allergy to egg products or neomycin No prior adverse reaction to tetanus toxoid-containing vaccines Other: No significant comorbid medical function No uncontrolled infection No unstable diabetes mellitus No uncontrolled thyroid function abnormalities No other malignancy within the past 5 years except basal cell carcinoma or adequately treated carcinoma in situ of the cervix No other medical illness or mental status that would preclude study participation No prior severe toxicity to adjuvant chemotherapy Not pregnant or nursing Negative pregnancy test Fertile patients must use effective contraception during and for at least 3 months after study participation PRIOR CONCURRENT THERAPY: Biologic therapy: No prior CEA-directed immunotherapy No other concurrent immunotherapy Chemotherapy: At least 6 months since prior adjuvant chemotherapy No prior chemotherapy for metastatic disease No other concurrent chemotherapy Endocrine therapy: No concurrent daily use of systemic steroids No concurrent nonsubstitutional hormonal therapy Radiotherapy: No prior radiotherapy to more than 50% of all nodal groups No concurrent radiotherapy except for palliative purposes involving less than 20% of bone marrow reserve Surgery: No prior major organ allograft Recovered from prior surgery Other: At least 28 days since prior investigational products No other concurrent investigational products