Context: Surgery remains the standard treatment of rectal cancer. The risk of local recurrence is still a serious problem with an incidence of between 15 and 45%. This depends on the initial TNM stage and the surgical technique. In order to optimally improve local control and survival of the patients, radiotherapy has become an unavoidable adjuvant treatment in specific situations.
Isolated radiotherapy: For locally advanced cancers (T3 or T4), pre-surgical radiotherapy followed by curative surgery is the standard treatment because of the improvement in global survival and good local control that has recently been confirmed. With radiotherapy it is also possible to schedule conservative sphincter surgery in the case of low rectal lesions and permit surgery of initially inoperable lesions. THE CONCOMITANT ASSOCIATION OF RADIOTHERAPY AND CHEMOTHERAPY DURING THE PRE-SURGICAL PERIOD: In rare cases in which the tumour stage was underestimated in the pre-surgical controls, post-surgical concomitant radio-chemotherapy is required. In cases in which surgery was performed first line, in the presence of histological factors of poor prognosis, post-surgical radio-chemotherapy is warranted. In the United States, the reference chemotherapy used in this association is 5 FU in continuous intravenous infusion. In the rare cases of contraindication for surgery, exclusive concomitant radio-chemotherapy is an appropriate solution, even if no treatment has been validated in this indication. Palliative surgery can be proposed in supplement: usually a colostomy or, more rarely excision using the endorectal route.
Medical treatment: Exclusive radio-chemotherapy has only demonstrated interest in the palliative treatment of inoperable loco-regional relapses that have already undergone radiation or in metastatic stages as in colon cancers. Currently post-surgical chemotherapy is recommended in stage III cancer of the rectum as in colon cancers at the same stage.