Vaccine Therapy, Cyclophosphamide, and Cetuximab in Treating Patients With Metastatic or Locally Advanced Pancreatic Cancer

DISEASE CHARACTERISTICS:

* Histologically confirmed ductal adenocarcinoma of the pancreas

  * Mixed adenocarcinoma tumors eligible provided the predominant invasive component of the tumor is adenocarcinoma
* The following histologic diagnoses are not eligible:

  * Adenosquamous
  * Squamous cell
  * Colloid
  * Islet cell
  * Serous or mucinous cystadenoma or cystadenocarcinoma
  * Carcinoid
  * Small or large cell carcinoma
  * Intraductal oncocytic papillary neoplasms
  * Osteoclast-like giant cell tumors
  * Acinar cell carcinoma
  * Pancreatoblastoma
  * Solid pseudopapillary tumors
  * Undifferentiated small cell carcinoma
  * Nonepithelial tumors (sarcoma, gastrointestinal stromal tumor, lymphoma)
  * Adenocarcinomas of the ampulla, distal bile duct, or duodenum
* Metastatic or locally advanced disease that is refractory to standard therapy OR for which patient refused standard therapy
* Measurable disease defined as ≥ 1 lesion unidimensionally measured as ≥ 20 mm by conventional techniques or ≥ 10 mm by spiral CT scan

  * No nonmeasurable disease only including, but not limited to, the following:

    * Bone lesions
    * Leptomeningeal disease
    * Ascites
    * Pleural or pericardial effusion
    * Inflammatory breast disease
    * Lymphangitis cutis/pulmonis
    * Abdominal masses that are not confirmed and followed by imaging techniques
    * Cystic lesions
* No known active or untreated brain metastases

PATIENT CHARACTERISTICS:

* ECOG performance status 0-1
* WBC ≥ 3,500/mm\^3
* Absolute neutrophil count ≥ 1,500/mm\^3
* Hemoglobin ≥ 9 g/dL
* Platelet count ≥ 90,000/mm\^3
* Creatinine ≤ 2.0 mg/dL
* Bilirubin ≤ 2 mg/dL
* ALT and AST ≤ 5 times upper limit of normal (ULN)
* Alkaline phosphatase ≤ 5 times ULN
* No active infection
* No uncontrolled medical condition that would potentially increase the risk of toxicities or complications of study therapy
* No gastrointestinal tract disease resulting in an inability to take oral medication or a requirement for IV alimentation
* No active peptic ulcer disease
* Not pregnant or nursing
* Negative pregnancy test
* Fertile patients must use effective contraception during and for 4 weeks after completion of study treatment
* No other malignancy within the past 5 years except for nonmelanomatous skin cancer, superficial bladder cancer, or carcinoma in situ of the cervix
* HIV negative
* No active autoimmune disease or prior autoimmune disease requiring medical treatment with systemic immunosuppressants including any of the following:

  * Inflammatory bowel disease
  * Systemic vasculitis
  * Scleroderma
  * Psoriasis
  * Multiple sclerosis
  * Hemolytic anemia or immune thrombocytopenia
  * Rheumatoid arthritis
  * Systemic lupus erythematosus
  * Sjögren's syndrome
  * Sarcoidosis
  * Asthma or chronic obstructive pulmonary disease that does not require systemic corticosteroids or routine use of inhaled steroids allowed
* No known or suspected hypersensitivity to sargramostim (GM-CSF), cyclophosphamide, pentastarch, corn, or DMSO
* No prior severe infusion reaction (\> grade 3) to a monoclonal antibody

PRIOR CONCURRENT THERAPY:

* See Disease Characteristics
* More than 1 month since prior adjuvant chemotherapy
* More than 4 weeks since prior surgery except for minor procedures (e.g., dental work, skin biopsy) and biliary stent placement
* No prior surgical procedures affecting absorption
* More than 4 weeks since prior radiotherapy
* More than 1 month since prior participation in an investigational new drug study
* No unresolved chronic toxicity (except alopecia) from prior anticancer therapy
* More than 28 days since prior systemic steroids
* No concurrent systemic steroids or immunosuppressive drugs

  * Topical, inhaled, and intra-articular steroids allowed
* No other concurrent anticancer vaccine therapy
* No other concurrent chemotherapy, immunotherapy, radiotherapy, gene therapy, biologic therapy, or investigational therapy