Inclusion Criteria:

- All patients 18 years of age or older, with biopsy proven T3-4N0-2M0 rectal cancer
are eligible.

- life expectancy of at least 2 years.

- Zubrod performance status of 0-2.

- Patients must be able to sign an informed consent.

- adequate bone marrow function: peripheral granulocyte count of > 1,500 cells/mm3 and
platelet count >100,000/mm3, hemoglobin > 10 gm/dl and absence of a regular red blood
cell transfusion requirement.

- adequate hepatic function with a total serum bilirubin < 1.5 x ULN; alkaline
phosphatase, ALAT, and ASAT < 2.5 x ULN; and adequate renal function as defined by a
calculated creatinine clearance > 50 ml/min [Cockroft-Gault].

- other initial cancer diagnosis more than five years ago without evidence of residual
or recurrent disease

- prior diagnosis of squamous or basal cell carcinoma of skin,no active disease at the
time of enrollment.

Exclusion Criteria:

- known metastases

- Pregnant or lactating women. Women/men of childbearing potential not using a
reliable and appropriate contraceptive method.

- may receive no other concurrent chemotherapy or radiation therapy during this trial.

- severe medical problems such as uncontrolled diabetes mellitus or cardiovascular
disease or active infections

- Prior pelvic radiation

- known active inflammatory bowel disease, Crohn's disease or ulcerative colitis.

- medical conditions that would preclude the patient from definitive surgery at the end
of concurrent chemoradiation

- Serious, uncontrolled, concurrent infection(s).

- Prior severe reaction to fluoropyrimidine therapy, or known hyper-sensitivity to
5-fluorouracil or known dihydropyrimidine dehydrogenase (DPD) deficiency.

- Treatment for other carcinomas within the last five years, except cured non-melanoma
skin and treated in-situ cervical cancer.

- Participation in any investigational drug study within 4 weeks preceding the start of
study treatment.

- Clinically significant cardiac disease or myocardial infarction within the last 12
months.

- History of uncontrolled seizures, central nervous system disorders or psychiatric
disability judged by the investigator to be clinically significant, precluding
informed consent, or interfering with compliance of oral drug intake.

- Other serious uncontrolled medical conditions that the investigator feels might
compromise study participation.

- Major surgery <4 weeks of the start of study treatment, without complete recovery.

- Lack of physical integrity of the upper gastrointestinal tract or malabsorption
syndrome.

- Known, existing uncontrolled coagulopathy

- Any of the following laboratory values:

- Abnormal hematologic values (neutrophils < 1.5 x 10^9/L, platelet count < 100 x
10^9/L, hemoglobin < 10 gm/dl)

- Impaired renal function (estimated creatinine clearance <50 ml/min as calculated
with Cockroft-Gault equation.

- Serum total bilirubin > 1.5 x upper normal limit.

- ALAT, ASAT > 2.5 x upper normal limit (or > 5 x upper normal limit in the case
of liver metastases).

- Alkaline phosphatase > 2.5 x upper normal limit (or > 5 x upper normal limit in
the case of liver metastases or > 10 x upper normal limit in the case of bone
disease).

- Unwillingness to give written informed consent.

- Unwillingness to participate or inability to comply with the protocol for the
duration of the study.

- History of allergic reactions, hypersensitivity reactions to aspirin, nonsteroidal
anti-inflammatory drugs (NSAIDs), or sulfonamides