Inclusion Criteria:

- Patients with histologically confirmed adenocarcinoma of the rectum:
EUS stage T3 or T4 or N1 disease are eligible (includes T3 N0, T3 N1, T4 N0, T4 N1, T1-4
N1). Rectal cancers will be defined as those whose distal border extends to within 12cm
of the anal verge.

- Age >= 18.

- Karnofsky performance status >= 70.

- Creatinine within normal institutional limits or creatinine clearance >
60mL/min/1.73m2 for patients with serum creatinine levels above institutional normal.

- Negative urine pregnancy test if a woman of child bearing potential (WOCBP).

- WOCBP must have a negative serum or urine pregnancy test (minimum sensitivity 25 IU/L
or equivalent units of HCG) within 72 hours prior to the start of study medication.

- WOCBP must be using an adequate method of contraception to avoid pregnancy throughout
the treatment.

- Ability to swallow pills without difficulty.

- No prior pelvic or whole abdominal radiotherapy.

- Patients must have adequate organ and marrow function as defined below:

Leukocyte count > 3,500. Platelet count > 100,000. SGOT, SGPT, Alk. Phos: < 2.5x
institutional upper limits of normal. Total bilirubin < 1.5x institutional normal
institutional limits.

Exclusion Criteria:- Metastatic (M1) or stage IV disease.

- Uncontrolled intercurrent illness including, but not limited to, ongoing or active
infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac
arrhythmia, or psychiatric illness/social situations that would limit compliance with
study requirements.

- Patients with a concurrent malignancy or previous malignancy within 5 years of
screening will be excluded from this study; with the exception of patients with
concurrent or previous non-melanoma skin cancer, hematolymphoid malignancy or
carcinoma in-situ of the cervix, who may be included at the investigator's
discretion.

- WOCBP who is pregnant or breastfeeding.

- A history of C225 or other therapy that targeted the EGF receptor.

- A history of prior anti-cancer murine monoclonal antibody therapy.

- Inability to sign written consent.

- WOCBP who are unwilling or unable to use an acceptable method to avoid pregnancy for
the entire study period and for up to 4 weeks after the study. Subjects who are men
must also agree to use effective contraception.