Cetuximab, 5-FU and Radiation as Neoadjuvant Therapy for Patients With Locally Advanced Rectal Cancer

Inclusion Criteria: * Histologically confirmed adenocarcinoma of the rectum that begins within 15cm of the anal verge as determined by sigmoidoscopy and/or colonoscopy, with no evidence of distant metastatic disease. A complete colonoscopy to the cecum is recommended prior to initiating protocol therapy. * Staging with transrectal ultrasound or endorectal coil Magnetic resonance imaging (MRI) to confirm clinical stage of T3 or T4 or lymph node positive rectal adenocarcinoma * Tumor is K-ras wildtype by method of choice at respective institution (testing codons 12 and 13) * Performance status: Eastern Cooperative Oncology Group Performance Score (ECOG PS) less than or equal to 2 * 18 years of age or older * No evidence of metastatic disease by abdominal/pelvic (Computed tomography) CT and chest imaging * Adequate bone marrow, renal,and hepatic function as outlined in protocol * All patients will be evaluated by a surgeon and considered a candidate for definitive surgery * Coumadin or heparin management for line care of other indications is permitted. The International Normalised Ratio (INR) will be monitored weekly in patients taking coumadin. Exclusion Criteria: * Prior treatment for this malignancy * Prior history of pelvic radiation therapy * Prior history of 5-FU based or EGFR receptor inhibitor therapy * Prior history of an allergic reaction to a monoclonal antibody * Uncontrolled serious medical or psychiatric illness * Significant history of uncontrolled cardiac disease * Sexually active women of childbearing potential must use an effective method of birth control during the course of the study * Unwilling to agree to pre and post-cetuximab sigmoidoscopy and biopsy