DISEASE CHARACTERISTICS:

• Histologically confirmed adenocarcinoma of the colon or rectum

  • Metastatic disease limited to the liver (no extrahepatic metastatic deposits)

• Underwent prior complete hepatic metastasectomy and is presently without evidence of cancer (no gross disease following surgery)

  • No radiographic evidence of colorectal cancer at enrollment

• Patients* may receive adjuvant systemic chemotherapy of colorectal cancer including, but not limited to, any of the following:

  • Combinations of cytotoxics such as fluoropyrimidines (fluorouracil and capecitabine), irinotecan hydrochloride, or oxaliplatin
  • Biologics with known activity against colorectal cancer such as bevacizumab and cetuximab NOTE: *Patients who are precluded from receiving such therapy secondary to toxicity or who refuse standard chemotherapy are also eligible

• Administration of the investigational product needs to be planned for 1-3 months after the last course of chemotherapy or liver resection

  • At least 1 month and no more than 3 months after the last course of systemic therapy or liver resection
• No colorectal cancer involving extrahepatic sites including lungs, bones, CNS, or peritoneum

PATIENT CHARACTERISTICS:

Inclusion criteria:

• ECOG performance status 0-1
• WBC ≥ 3,500/mm^3
• ANC > 1,000/mm^3
• Platelet count > 100,000/mm^3
• Hemoglobin ≥ 9 g/dL
• Serum creatinine < 2.0 mg/dL AND creatinine clearance > 60 mL/min
• Serum bilirubin < 2.0 mg/dL (serum bilirubin 2.0 is acceptable in the setting of known Gilbert syndrome)
• AST and ALT < 3.0 times upper limit of normal (ULN)
• Alkaline phosphatase < 4 times ULN
• Fertile patients must use effective contraception during and for 28 days after completion of study treatment
• Negative pregnancy test
• Asthma or chronic obstructive pulmonary disease that does not require daily systemic corticosteroids allowed

Exclusion criteria:

• Prior or currently active autoimmune disease requiring management with systemic immunosuppression, including, but not limited to, any of the following:

  • Inflammatory bowel disease
  • Systemic vasculitis
  • Scleroderma
  • Psoriasis
  • Multiple sclerosis
  • Hemolytic anemia
  • Immune-mediated thrombocytopenia, rheumatoid arthritis, systemic lupus erythematosus, Sjögren syndrome, sarcoidosis, or other rheumatologic disease
• Active or uncontrolled medical or psychosocial problems that could be complicated by the patient's participation in the study
• Evidence of active acute or chronic infection
• History of other malignancies within the prior five years (excluding a history of carcinoma in situ of the cervix, superficial nonmelanoma skin cancer, and superficial bladder cancer)
• Known or suspected hypersensitivity to sargramostim (GM-CSF), cyclophosphamide, pentastarch, corn, or DMSO

PRIOR CONCURRENT THERAPY:

• See Disease Characteristics
• Recovered from all prior therapy (alopecia allowed)
• More than 28 days since prior anticancer therapy, including prior systemic chemotherapy, radiotherapy, or biologic therapy

• More than 28 days since prior systemic corticosteroid treatment via the oral, intramuscular, or intravenous routes

  • Suppositories with a steroid component are not allowed during the 28 days prior to study dosing and for the subsequent 28 days
  • Steroids administered via the respiratory (intranasal or inhaled) or intraarticular route that are not immunosuppressive are acceptable
  • Topical steroids of a strength up to 1% allowed

• More than 28 days since prior surgery

  • Minor procedures (dental work or skin biopsy) and biliary stent placement allowed
• More than 28 days since other prior anti-cancer vaccine therapy or participation in an investigational new drug trial
• Concurrent hormonal therapy, including hormone replacement therapy in postmenopausal women and birth control pills, and supportive therapy with bisphosphonates allowed