A Randomised Trial of Preoperative Radiotherapy for Stage T3 Adenocarcinoma of Rectum

Inclusion Criteria: All of the following must apply: * Pathologically documented and clinically resectable adenocarcinoma of the rectum. * The patient must be considered by the surgeon to be suitable for a curative resection. * The patient must be considered by the radiation oncologist to have no contraindication to pre-operative radiotherapy. * Clinical T3 stage tumour on endorectal ultrasound or MRI. When endorectal ultrasound cannot be performed satisfactorily due to a technical reason, such as stenosis or proximity of the tumour, and MRI is not available, infiltration of perirectal fat on CT scan is also acceptable. * Tumour with lower border within 12 cm from anal verge on rigid sigmoidoscopy. * ECOG performance status 0, 1 or 2. * Adequate bone marrow function with neutrophil count at least 1.5 x 109/L and platelet count at least 100 x 109/L. * Adequate liver function with bilirubin and alanine aminotransferase (ALT) \<= 1.5 times the upper limit of normal. * Adequate renal function with serum creatinine \<= 1.5 times the upper limit of normal. * Accessibility for treatment and follow-up. * Written informed consent. Exclusion Criteria: * None of the following must apply: * Evidence of distant metastases. * Recurrent rectal cancer. * Unstable cardiac disease or clinically significant active infection. * Other cancer in the last 5 years except treated non-melanoma skin cancer or carcinoma in situ of the cervix. * Pregnant or lactating females or female patients of childbearing potential who have not been surgically sterilized or are without adequate contraceptive measures. * Contraindication to insertion of a suitable indwelling venous catheter e.g. implantable central venous device (infuse-a-port), Hickman catheter or peripherally inserted central catheter. * Prior pelvic or abdominal radiotherapy.