Inclusion Criteria:

- Histologically confirmed adenocarcinoma of the rectum

- AJCC/UICC pathologic stages of cT3-4 or cN plus

- Male or female patients, 18 years of age or older

- Be ambulatory and have an Eastern Cooperative Oncology Group (ECOG) performance
status 0-1.

- No prior chemotherapy, radiotherapy and immunotherapy

- Adequate major organ functions as following: Hematopoietic function: ANC (absolute
neutrophil count)1,500/mm3, Platelet 100,000/mm3, and Hepatic function: serum
bilirubin < 1.5 x ULN, AST/ALT levels < 2.5 x ULN, and Renal function: serum
creatinine < 1.5 x ULN or Ccr 50 ml/min by Cockcroft formula

- Be willing and able to comply with the protocol for the duration of the study.

- Give written informed consent prior to study-specific screening procedures, with the
understanding that the patient has the right to withdraw from the study at any time,
without prejudice.

Exclusion Criteria:

- Any histologic feature other than adenocarcinoma or arisen from chronic inflammatory
bowel disease

- Patients treated with previous surgery, chemotherapy and/or radiotherapy

- Uncontrolled or severe cardiovascular disease: New York Heart Association class III
or IV heart disease, and Unstable angina or myocardial infarction within the past 6
months, and History of significant ventricular arrhythmia requiring medication with
antiarrhythmics or significant conduction system abnormality.

- Serious concurrent infection or nonmalignant illness that is uncontrolled or whose
control may be jeopardized by complications of study therapy.

- Other malignancy within the past 5 years except non-melanomatous skin cancer or
carcinoma in situ of the cervix.

- Organ allografts requiring immunosuppressive therapy.

- Psychiatric disorder or uncontrolled seizure that would preclude compliance.

- Pregnant, nursing women or patients with reproductive potential without
contraception.

- Patients receiving a concomitant treatment with drugs interacting with 5-FU or
irinotecan such as flucytosine, phenytoin, or warfarin et al.

- Prior unanticipated severe reaction to fluoropyrimidine therapy, or known
dihydropyrimidine dehydrogenase (DPD) deficiency.

- Known hypersensitivity to any of the components of the study medications.

- Received any investigational drug or agent within 4 weeks before beginning treatment
with study drug.