A Study for Short Preoperative Chemoradiotherapy for Resectable Rectal Carcinoma

Inclusion Criteria:

* Pathologically confirmed diagnosis of adenocarcinoma of the rectum by biopsy technique that does not completely excise the lesion (e.g., fine needle aspiration, core needle biopsy)
* Located up to 15 cm from the anal verge with no extension of malignant disease into the anal canal
* Stage IIIB-IIIC disease (T3-T4, N0-2, M0)(i.e., without evidence of distant metastases) tumor as determined by the following assessments:Colonoscopy and biopsy within the past 8 weeks; History/physical examination (including medication history screen for contraindications) within the past 8 weeks; Contrast-enhanced imaging of the abdomen and pelvis either by CT, MRI, or PET-CT (whole body preferred) within the past 8 weeks
* Chest x-ray (or CT) of the chest within the past 8 weeks to exclude distant metastases (except for patients who have had whole body PET-CT)
* Transrectal ultrasound (TRUS) within the past 8 weeks required to establish tumor stage
* TRUS not required if clinical exam, CT of the pelvis, and/or MRI demonstrates T4 lesion
* No synchronous primary colon carcinoma
* No evidence of distant metastases (M1)
* ANC ≥ 1,800/mm³
* Platelet count ≥ 100,000/mm³
* Hemoglobin ≥ 8.0 g/dL (transfusion or other intervention to achieve hemoglobin ≥ 8.0 g/dL allowed)
* AST \< 2.5 times upper limit of normal (ULN)
* Alkaline phosphatase \< 2.5 times ULN
* Bilirubin ≤ 1.5 times ULN
* Creatinine clearance \> 50 mL/min
* Not pregnant or nursing
* Negative pregnancy test
* Fertile patients must use effective contraception
* No prior invasive malignancy except nonmelanoma skin cancer unless disease free for a minimum of 3 years

Exclusion Criteria:

* Severe, active comorbidity, defined as follows:
* Unstable angina and/or congestive heart failure requiring hospitalization within the past 12 months
* Transmural myocardial infarction within the past 6 months
* Acute bacterial or fungal infection requiring intravenous antibiotics
* Chronic obstructive pulmonary disease exacerbation or other respiratory illness requiring hospitalization or precluding study therapy within the past 30 days
* Hepatic insufficiency resulting in clinical jaundice and/or coagulation defects
* AIDS
* Evidence 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
* Known, existing uncontrolled coagulopathy, unless clinically stable on anticoagulation therapy for ≥ 2 weeks
* Evidence of peripheral neuropathy ≥ grade 2
* Prior allergic reaction to capecitabine
* Lack of physical integrity of the gastrointestinal tract (i.e., severe Crohn disease that results in malabsorption; significant bowel resection that would make one concerned about the absorption of capecitabine) or malabsorption syndrome that would preclude feasibility of oral chemotherapy (i.e., capecitabine)