The standard treatment of locally advanced but resectable cancer in the middle or lower rectum is preoperative radio-chemotherapy and in the upper part initial surgery. The clinical benefit from radio-chemotherapy is primarily through a reduction in local relapse but the treatment is associated with acute toxicity and long term functional dysfunction. Subsequently, it is important to select patients with high risk of local relapse. Intense systemic combination chemotherapy reduces the risk of distant relapse and increases survival in the postoperative setting. The biological rationale is eradication of micrometastases and hence it may be anticipated that earlier, i.e. neoadjuvant, combination therapy may improve systemic control.
