Locally advanced rectal cancer is a cancer of the rectum that has a high risk of recurrence. In general, patients with this condition would benefit from further treatment in addition to surgery. The additional treatment, radiotherapy and chemotherapy, has been shown to improve the chance of cure. It has also been shown that radiotherapy given with chemotherapy before surgery, and chemotherapy given after surgery will provide better chance of controlling this condition. Doctors are looking for better ways to treat people with locally advanced rectal cancer. This research project tested a new combination of chemotherapy and radiotherapy. It involved an 11-week treatment of chemotherapy known as FOLFOX and radiotherapy. The ultimate aim of this study is to see whether this schedule of chemo-radiotherapy provides better control of the cancer in the rectum, and to also see if this chemotherapy combination is more effective (than standard chemotherapy) in stopping the cancer developing in other parts of the body. The purpose of this trial is to make sure that this treatment combination (of chemotherapy and radiotherapy prior to surgery) is safe and effective before testing it further in another study against the standard of treatment.