Inclusion Criteria

DISEASE CHARACTERISTICS:

- Histologically or cytologically confirmed unresectable adenocarcinoma of the pancreas

- Including subtotal resection and gross residual disease

- No microscopic residual disease only

- Measurable disease is not required

- Disease is encompassable within standard radiotherapy fields for pancreatic cancer

- No evidence of metastatic disease outside of the planned radiotherapy field

- No cystadenocarcinoma of the pancreas or pancreatic tumors of neuroendocrine origin

- No distant metastases (i.e., liver or lung metastases or peritoneal spread)

- No history or known presence of CNS metastases

PATIENT CHARACTERISTICS:

- ECOG performance status 0-1

- ANC ≥ 1,500/mm³

- Hemoglobin ≥ 9.0 g/dL

- Platelet count ≥ 100,000/mm³

- Total bilirubin ≤ 3 times upper limit of normal (ULN)* NOTE: *Biliary stent placement
or surgical bypass should be considered prior to treatment if impending bile duct
obstruction by tumor

- AST ≤ 3 times ULN

- Creatinine ≤ 2.0 times ULN

- Magnesium normal

- Willing to return to an NCCTG institution for follow-up

- Not pregnant or nursing

- Negative pregnancy test

- Fertile patients must use effective contraception during and for at least 6 months
after treatment with panitumumab

- No prior or concurrent malignancy unless disease-free ≥ 3 years except for
non-melanoma skin cancer, carcinoma in situ of the cervix, or organ confined prostate
cancer with Gleason score < 7

- No nausea or vomiting > grade 1

- No uncontrolled intercurrent illness including, but not limited to, any the
following:

- Ongoing or active infection

- Psychiatric illness or social situations that would limit compliance with study
requirements

- No New York Heart Association clinically significant cardiovascular disease ≥ grade
2, including any of the following within the past year:

- Myocardial infarction

- Unstable angina

- Symptomatic congestive heart failure

- Serious, uncontrolled cardiac arrhythmia

- No known HIV positivity

- No known hepatitis C virus or acute or chronic active hepatitis B infection

- Adequate oral nutrition

PRIOR CONCURRENT THERAPY:

- More than 21 days since prior laparotomy

- No prior anti-epidermal growth factor receptor (EGFR) antibody therapy (e.g.,
cetuximab)

- No prior small molecule EGFR inhibitors (e.g., gefitinib, erlotinib, or lapatinib)

- No prior radiotherapy that would overlap with planned radiotherapy fields

- No prior or other concurrent chemotherapy

- No prior or other concurrent biologic therapy

- More than 4 weeks since prior and no concurrent or planned participation in another
experimental drug study except studies with specific interventions intended to treat
rashes associated with EGFR agents (e.g., N05C4)

- No concurrent enteral hyperalimentation

- No concurrent chronic immunosuppressive agents (e.g., methotrexate, cyclosporine, or
corticosteroids)

- No concurrent colony-stimulating factors during the first course of therapy

- No other concurrent immunotherapy or radiotherapy